diff --git a/Include/Fledasty/Strings/String.h b/Include/Fledasty/Strings/String.h
new file mode 100644
index 0000000..cdd6e79
--- /dev/null
+++ b/Include/Fledasty/Strings/String.h
@@ -0,0 +1,60 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * -----------------------------------------------------------------------------
+ * File: String.h
+ * Description:
+ *  This file contains the String structure and the functions for modifying it. 
+ *  It includes functions to append, Insert at index, insert before character,
+ *  insert before string, insert after character, insert after string, replace,
+ *  copy, pop, remove, remove range, clear, check if contains string, check if
+ *  empty. 
+ * 
+ * Author: Mineplay
+ * -----------------------------------------------------------------------------
+ */
+#ifndef FLEDASTY_STRING
+#define FLEDASTY_STRING
+
+#include <stddef.h>
+#include <stdbool.h>
+ 
+#include "../Utils/Error.h"
+
+typedef struct {
+    size_t size, capacity;
+    char *character_string;
+} FledastyString;
+
+FledastyError fledasty_string_free(FledastyString *current_string);
+
+FledastyError fledasty_string_append(FledastyString *current_string, char *character_string, const size_t character_string_size);
+FledastyError fledasty_string_insert_at_index(FledastyString *current_string, const size_t index, char *character_string, const size_t character_string_size);
+FledastyError fledasty_string_insert_before_string(FledastyString *current_string, char *before_character_string, const size_t before_character_string_size, char *character_string, const size_t character_string_size);
+FledastyError fledasty_string_insert_after_string(FledastyString *current_string, char *after_character_string, const size_t after_character_string_size, char *character_string, const size_t character_string_size);
+
+FledastyError fledasty_string_pop(FledastyString *current_string);
+FledastyError fledasty_string_remove(FledastyString *current_string, char *character_string, const size_t character_string_size);
+FledastyError fledasty_string_remove_range(FledastyString *current_string, const size_t start_index, const size_t end_index);
+
+FledastyError fledasty_string_replace_string(FledastyString *current_string, char *replace_character_string, const size_t replace_character_string_size, char *character_string, const size_t character_string_size);
+
+FledastyError fledasty_string_clear(FledastyString *current_string);
+FledastyError fledasty_string_shrink_to_fit(FledastyString *current_string);
+
+bool fledasty_string_has_string(const FledastyString *current_string, char *character_string, const size_t character_string_size);
+static inline bool fledasty_string_is_empty(const FledastyString *current_string) { return current_string == NULL || current_string->size == 0; }
+
+size_t fledasty_string_get_size(const char *character_string);
+
+#endif
diff --git a/Src/Strings/String.c b/Src/Strings/String.c
new file mode 100644
index 0000000..d7b6e08
--- /dev/null
+++ b/Src/Strings/String.c
@@ -0,0 +1,299 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * -----------------------------------------------------------------------------
+ * File: String.c
+ * Description:
+ *  This file contains the functions for modifying the String. It includes 
+ *  functions to append, Insert at index, insert before character,
+ *  insert before string, insert after character, insert after string, replace,
+ *  copy, pop, remove, remove range, clear, check if contains string, check if
+ *  empty. 
+ * 
+ * Author: Mineplay
+ * -----------------------------------------------------------------------------
+ */
+#include "../../Include/Fledasty/Strings/String.h"
+
+#include <Hallocy/Core/Allocator.h>
+#include <Hallocy/Core/Memory.h>
+#include <Hallocy/Utils/Error.h>
+
+FledastyError fledasty_string_free(FledastyString *current_string) {
+    if (current_string == NULL) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    if (hallocy_free(current_string->character_string) != HALLOCY_ERROR_NONE) {
+        return FLEDASTY_ERROR_FAILED_ALLOCATION;
+    }
+
+    current_string->character_string = NULL;
+    return FLEDASTY_ERROR_NONE;
+}
+
+FledastyError fledasty_string_append(FledastyString *current_string, char *character_string, const size_t character_string_size) {
+    if (current_string == NULL || character_string == NULL || character_string_size == 0) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    if (current_string->capacity <= current_string->size + character_string_size) {
+        current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size + 1;
+        current_string->character_string = (char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(char));
+
+        if (current_string->character_string == NULL) {
+            return FLEDASTY_ERROR_FAILED_ALLOCATION;
+        }
+    }
+
+    hallocy_copy_memory(current_string->character_string + current_string->size, character_string, character_string_size);
+
+    current_string->size += character_string_size;
+    current_string->character_string[current_string->size] = '\0';
+
+    return FLEDASTY_ERROR_NONE;
+}
+
+FledastyError fledasty_string_insert_at_index(FledastyString *current_string, const size_t index, char *character_string, const size_t character_string_size) {
+    if (current_string == NULL || character_string == NULL || character_string_size == 0) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    if (index > current_string->size) {
+        return FLEDASTY_ERROR_INDEX_OUT_OF_RANGE;
+    }
+
+    if (current_string->capacity <= current_string->size + character_string_size) {
+        current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size;
+        current_string->character_string = (char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(char));
+
+        if (current_string->character_string == NULL) {
+            return FLEDASTY_ERROR_FAILED_ALLOCATION;
+        }
+    }
+
+    hallocy_move_memory(current_string->character_string + (index + character_string_size), current_string->character_string + index, current_string->size - index);
+    hallocy_copy_memory(current_string->character_string + index, character_string, character_string_size);
+    
+    current_string->size += character_string_size;
+    current_string->character_string[current_string->size] = '\0';
+    return FLEDASTY_ERROR_NONE;
+}
+
+FledastyError fledasty_string_insert_before_string(FledastyString *current_string, char *before_character_string, const size_t before_character_string_size, char *character_string, const size_t character_string_size) {
+    if (current_string == NULL || before_character_string == NULL  || before_character_string_size == 0 || character_string == NULL || character_string_size == 0) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    size_t index = 0;
+    while (index < (current_string->size - before_character_string_size)) {
+        if (hallocy_compare_memory(current_string->character_string + index, before_character_string, before_character_string_size)) {
+            if (current_string->capacity <= current_string->size + character_string_size) {
+                current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size + 1;
+                current_string->character_string = (char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(char));
+
+                if (current_string->character_string == NULL) {
+                    return FLEDASTY_ERROR_FAILED_ALLOCATION;
+                }
+            }
+        
+            hallocy_move_memory(current_string->character_string + (index + character_string_size), current_string->character_string + index, current_string->size - index);
+            hallocy_copy_memory(current_string->character_string + index, character_string, character_string_size);
+            
+            current_string->size += character_string_size;
+            current_string->character_string[current_string->size] = '\0';
+
+            return FLEDASTY_ERROR_NONE;
+        }
+
+        index += 1;
+    }
+
+    return FLEDASTY_ERROR_VALUE_NOT_FOUND;   
+}
+
+FledastyError fledasty_string_insert_after_string(FledastyString *current_string, char *after_character_string, const size_t after_character_string_size, char *character_string, const size_t character_string_size) {
+    if (current_string == NULL || after_character_string == NULL || after_character_string_size == 0 || character_string == NULL || character_string_size == 0) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    size_t index = 0;
+    while (index < (current_string->size - after_character_string_size)) {
+        if (hallocy_compare_memory(current_string->character_string + index, after_character_string, after_character_string_size)) {
+            if (current_string->capacity <= current_string->size + character_string_size) {
+                current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size + 1;
+                current_string->character_string = (char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(char));
+
+                if (current_string->character_string == NULL) {
+                    return FLEDASTY_ERROR_FAILED_ALLOCATION;
+                }
+            }
+        
+            index += after_character_string_size;
+            hallocy_move_memory(current_string->character_string + (index + character_string_size), current_string->character_string + index, current_string->size - index + 1);
+            hallocy_copy_memory(current_string->character_string + index, character_string, character_string_size);
+            
+            current_string->size += character_string_size;
+            current_string->character_string[current_string->size] = '\0';
+
+            return FLEDASTY_ERROR_NONE;
+        }
+
+        index += 1;
+    }
+
+    return FLEDASTY_ERROR_VALUE_NOT_FOUND;
+}
+
+FledastyError fledasty_string_pop(FledastyString *current_string) {
+    if (current_string == NULL) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    current_string->size -= 1;
+    current_string->character_string[current_string->size] = '\0';
+
+    return FLEDASTY_ERROR_NONE;
+}
+
+FledastyError fledasty_string_remove(FledastyString *current_string, char *character_string, const size_t character_string_size) {
+    if (current_string == NULL || character_string == NULL || character_string_size == 0) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    size_t index = 0;
+    while (index < (current_string->size - character_string_size)) {
+        if (hallocy_compare_memory(current_string->character_string + index, character_string, character_string_size)) {
+            hallocy_move_memory(current_string->character_string + index, current_string->character_string + index + character_string_size, current_string->size - (index + character_string_size));
+        
+            current_string->size -= character_string_size;
+            current_string->character_string[current_string->size] = '\0';
+
+            return FLEDASTY_ERROR_NONE;
+        }
+
+        index += 1;
+    }
+
+    return FLEDASTY_ERROR_VALUE_NOT_FOUND;
+}
+
+FledastyError fledasty_string_remove_range(FledastyString *current_string, const size_t start_index, const size_t end_index) {
+    if (current_string == NULL) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    if (start_index >= end_index || end_index >= current_string->size) {
+        return FLEDASTY_ERROR_INDEX_OUT_OF_RANGE;
+    }
+
+    hallocy_move_memory(current_string->character_string + start_index, current_string->character_string + end_index, current_string->size - end_index);
+
+    current_string->size -= end_index - start_index;
+    current_string->character_string[current_string->size] = '\0';
+
+    return FLEDASTY_ERROR_NONE;
+}
+
+FledastyError fledasty_string_replace_string(FledastyString *current_string, char *replace_character_string, const size_t replace_character_string_size, char *character_string, const size_t character_string_size) {
+    if (current_string == NULL || replace_character_string == NULL || replace_character_string_size == 0 || character_string == NULL || character_string_size == 0) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    size_t index = 0;
+    while (index < current_string->size - replace_character_string_size) {
+        if (hallocy_compare_memory(current_string->character_string + index, replace_character_string, replace_character_string_size)) {
+            const size_t new_size = current_string->size + (character_string_size - replace_character_string_size);
+            if (current_string->capacity <= new_size) {
+                current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size;
+                current_string->character_string = (char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(char));
+
+                if (current_string->character_string == NULL) {
+                    return FLEDASTY_ERROR_FAILED_ALLOCATION;
+                }
+            }
+
+            hallocy_move_memory(current_string->character_string + index + character_string_size, current_string->character_string + index + replace_character_string_size, current_string->size - (index + replace_character_string_size));
+            hallocy_copy_memory(current_string->character_string + index, character_string, character_string_size);
+
+            current_string->size = new_size;
+            current_string->character_string[current_string->size] = '\0';
+
+            return FLEDASTY_ERROR_NONE;
+        }
+
+        index += 1;
+    }
+
+    return FLEDASTY_ERROR_VALUE_NOT_FOUND;
+}
+
+FledastyError fledasty_string_clear(FledastyString *current_string) {
+    if (current_string == NULL) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    current_string->size = 0;
+    current_string->character_string[0] = '\0';
+
+    return FLEDASTY_ERROR_NONE;
+}
+
+FledastyError fledasty_string_shrink_to_fit(FledastyString *current_string) {
+    if (current_string == NULL) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    char *previous_string = current_string->character_string;
+
+    current_string->capacity = current_string->size + 1;
+    current_string->character_string = (char*)hallocy_malloc(current_string->capacity * sizeof(char*));
+    if (current_string->character_string == NULL) {
+        return FLEDASTY_ERROR_FAILED_ALLOCATION;
+    }
+
+    hallocy_copy_memory(current_string->character_string, previous_string, current_string->size);
+    current_string->character_string[current_string->size] = '\0';
+
+    if (hallocy_free(previous_string) != HALLOCY_ERROR_NONE) {
+        return FLEDASTY_ERROR_FAILED_ALLOCATION;
+    }
+
+    return FLEDASTY_ERROR_NONE;
+}
+
+bool fledasty_string_has_string(const FledastyString *current_string, char *character_string, const size_t character_string_size) {
+    if (current_string == NULL || character_string == NULL || character_string_size == 0) {
+        return false;
+    }
+
+    size_t index = 0;
+    while (index < current_string->size - character_string_size) {
+        if (hallocy_compare_memory(current_string->character_string + index, character_string, character_string_size)) {
+            return true;
+        }
+
+        index += 1;
+    }
+
+    return false;
+}
+
+size_t fledasty_string_get_size(const char *character_string) {
+    size_t size = 0;
+    while (character_string[size] != '\0') {
+        size += 1;
+    }
+
+    return size;
+}
diff --git a/Src/Strings/UTF8String.c b/Src/Strings/UTF8String.c
index be36e34..62bc3af 100644
--- a/Src/Strings/UTF8String.c
+++ b/Src/Strings/UTF8String.c
@@ -24,7 +24,6 @@
  * -----------------------------------------------------------------------------
  */
 #include "../../Include/Fledasty/Strings/UTF8String.h"
-#include "Fledasty/Utils/Error.h"
 
 #include <Hallocy/Core/Allocator.h>
 #include <Hallocy/Core/Memory.h>
@@ -57,6 +56,10 @@ FledastyError fledasty_utf8_string_append(FledastyUtf8String *current_string, un
     if (current_string->capacity <= current_string->size + character_string_size) {
         current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size + 1;
         current_string->character_string = (unsigned char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(unsigned char));
+
+        if (current_string->character_string == NULL) {
+            return FLEDASTY_ERROR_FAILED_ALLOCATION;
+        }
     }
 
     hallocy_copy_memory(current_string->character_string + current_string->size, character_string, character_string_size);
@@ -83,6 +86,10 @@ FledastyError fledasty_utf8_string_insert_at_index(FledastyUtf8String *current_s
     if (current_string->capacity <= current_string->size + character_string_size) {
         current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size;
         current_string->character_string = (unsigned char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(unsigned char));
+
+        if (current_string->character_string == NULL) {
+            return FLEDASTY_ERROR_FAILED_ALLOCATION;
+        }
     }
 
     hallocy_move_memory(current_string->character_string + (index + character_string_size), current_string->character_string + index, current_string->size - index);
@@ -103,17 +110,23 @@ FledastyError fledasty_utf8_string_insert_before_string(FledastyUtf8String *curr
     }
 
     size_t index = 0;
-    while (index < (current_string->size - before_character_string_size) && !hallocy_compare_memory(current_string->character_string + index, before_character_string, before_character_string_size)) {
+    while (index < (current_string->size - before_character_string_size)) {
         if (hallocy_compare_memory(current_string->character_string + index, before_character_string, before_character_string_size)) {
             if (current_string->capacity <= current_string->size + character_string_size) {
                 current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size + 1;
                 current_string->character_string = (unsigned char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(unsigned char));
+
+                if (current_string->character_string == NULL) {
+                    return FLEDASTY_ERROR_FAILED_ALLOCATION;
+                }
             }
         
             hallocy_move_memory(current_string->character_string + (index + character_string_size), current_string->character_string + index, current_string->size - index);
             hallocy_copy_memory(current_string->character_string + index, character_string, character_string_size);
             
             current_string->size += character_string_size;
+            current_string->character_string[current_string->size] = '\0';
+
             return FLEDASTY_ERROR_NONE;
         }
 
@@ -138,6 +151,10 @@ FledastyError fledasty_utf8_string_insert_after_string(FledastyUtf8String *curre
             if (current_string->capacity <= current_string->size + character_string_size) {
                 current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size + 1;
                 current_string->character_string = (unsigned char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(unsigned char));
+
+                if (current_string->character_string == NULL) {
+                    return FLEDASTY_ERROR_FAILED_ALLOCATION;
+                }
             }
         
             index += after_character_string_size;
@@ -145,6 +162,8 @@ FledastyError fledasty_utf8_string_insert_after_string(FledastyUtf8String *curre
             hallocy_copy_memory(current_string->character_string + index, character_string, character_string_size);
             
             current_string->size += character_string_size;
+            current_string->character_string[current_string->size] = '\0';
+
             return FLEDASTY_ERROR_NONE;
         }
 
@@ -190,6 +209,7 @@ FledastyError fledasty_utf8_string_remove(FledastyUtf8String *current_string, un
         
             current_string->size -= character_string_size;
             current_string->character_string[current_string->size] = '\0';
+
             return FLEDASTY_ERROR_NONE;
         }
 
@@ -212,6 +232,7 @@ FledastyError fledasty_utf8_string_remove_range(FledastyUtf8String *current_stri
 
     current_string->size -= end_index - start_index;
     current_string->character_string[current_string->size] = '\0';
+
     return FLEDASTY_ERROR_NONE;
 }
 
@@ -231,6 +252,10 @@ FledastyError fledasty_utf8_string_replace_string(FledastyUtf8String *current_st
             if (current_string->capacity <= new_size) {
                 current_string->capacity += (current_string->capacity > character_string_size) ? current_string->capacity : character_string_size;
                 current_string->character_string = (unsigned char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(unsigned char));
+
+                if (current_string->character_string == NULL) {
+                    return FLEDASTY_ERROR_FAILED_ALLOCATION;
+                }
             }
 
             hallocy_move_memory(current_string->character_string + index + character_string_size, current_string->character_string + index + replace_character_string_size, current_string->size - (index + replace_character_string_size));
@@ -238,8 +263,10 @@ FledastyError fledasty_utf8_string_replace_string(FledastyUtf8String *current_st
 
             current_string->size = new_size;
             current_string->character_string[current_string->size] = '\0';
+
             return FLEDASTY_ERROR_NONE;
         }
+
         index += 1;
     }
 
@@ -265,11 +292,18 @@ FledastyError fledasty_utf8_string_shrink_to_fit(FledastyUtf8String *current_str
     unsigned char *previous_string = current_string->character_string;
 
     current_string->capacity = current_string->size + 1;
-    current_string->character_string = (unsigned char*)hallocy_malloc(current_string->capacity);
+    current_string->character_string = (unsigned char*)hallocy_malloc(current_string->capacity * sizeof(unsigned char*));
+    if (current_string->character_string == NULL) {
+        return FLEDASTY_ERROR_FAILED_ALLOCATION;
+    }
+
     hallocy_copy_memory(current_string->character_string, previous_string, current_string->size);
     current_string->character_string[current_string->size] = '\0';
 
-    hallocy_free(previous_string);
+    if (hallocy_free(previous_string) != HALLOCY_ERROR_NONE) {
+        return FLEDASTY_ERROR_FAILED_ALLOCATION;
+    }
+    
     return FLEDASTY_ERROR_NONE;
 }
 
@@ -306,6 +340,10 @@ FledastyUtf8String fledasty_utf8_string_encode(const uint32_t *unicode, const si
             if (utf8_string.capacity <= string_index) {
                 utf8_string.capacity += (utf8_string.capacity > FLEDASTY_STRING_DEFAULT_ALLOCATION_SIZE) ? utf8_string.capacity : FLEDASTY_STRING_DEFAULT_ALLOCATION_SIZE;
                 utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+
+                if (utf8_string.character_string == NULL) {
+                    return utf8_string;
+                }
             }
 
             utf8_string.character_string[string_index] = unicode[index];
@@ -314,6 +352,10 @@ FledastyUtf8String fledasty_utf8_string_encode(const uint32_t *unicode, const si
             if (utf8_string.capacity <= string_index + 2) {
                 utf8_string.capacity += (utf8_string.capacity > FLEDASTY_STRING_DEFAULT_ALLOCATION_SIZE) ? utf8_string.capacity : FLEDASTY_STRING_DEFAULT_ALLOCATION_SIZE;
                 utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+                
+                if (utf8_string.character_string == NULL) {
+                    return utf8_string;
+                }
             }
 
             utf8_string.character_string[string_index] = 0xC0 | ((unicode[index] >> 6) & 0x07);
@@ -323,6 +365,10 @@ FledastyUtf8String fledasty_utf8_string_encode(const uint32_t *unicode, const si
             if (utf8_string.capacity <= string_index + 3) {
                 utf8_string.capacity += (utf8_string.capacity > FLEDASTY_STRING_DEFAULT_ALLOCATION_SIZE) ? utf8_string.capacity : FLEDASTY_STRING_DEFAULT_ALLOCATION_SIZE;
                 utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+                
+                if (utf8_string.character_string == NULL) {
+                    return utf8_string;
+                }
             }
 
             utf8_string.character_string[string_index] = 0xE0 | ((unicode[index] >> 12) & 0x07);
@@ -333,6 +379,10 @@ FledastyUtf8String fledasty_utf8_string_encode(const uint32_t *unicode, const si
             if (utf8_string.capacity <= string_index + 4) {
                 utf8_string.capacity += (utf8_string.capacity > FLEDASTY_STRING_DEFAULT_ALLOCATION_SIZE) ? utf8_string.capacity : FLEDASTY_STRING_DEFAULT_ALLOCATION_SIZE;
                 utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+
+                if (utf8_string.character_string == NULL) {
+                    return utf8_string;
+                }
             }
 
             utf8_string.character_string[string_index] = 0xF0 | ((unicode[index] >> 18) & 0x07);
@@ -361,6 +411,10 @@ uint32_t *fledasty_utf8_string_decode(const FledastyUtf8String *current_string,
     (*unicode_string_size) = 0;
     size_t index = 0;
     uint32_t *unicode_string = (uint32_t*)hallocy_malloc(current_string->size * sizeof(uint32_t));
+    if (unicode_string == NULL) {
+        return NULL;
+    }
+
     while (index < current_string->size) {
         if ((current_string->character_string[index] & 0xF0) == 0xF0) {
             unicode_string[*unicode_string_size] = ((current_string->character_string[index] & 0x07) << 18) | ((current_string->character_string[index + 1] & 0x3F) << 12) | ((current_string->character_string[index + 2] & 0x3F) << 6) | (current_string->character_string[index + 3] & 0x3F);
diff --git a/Tests/Main.c b/Tests/Main.c
index 264e5d2..b449818 100644
--- a/Tests/Main.c
+++ b/Tests/Main.c
@@ -28,6 +28,7 @@
 #include <Fledasty/Core/DoublyLinkedList.h>
 #include <Fledasty/Core/HashTable.h>
 #include <Fledasty/Strings/UTF8String.h>
+#include <Fledasty/Strings/String.h>
 #include <Fledasty/Algorithms/Hashing.h>
 
 static inline bool compare_integers(const int first_value, const int second_value) { return first_value == second_value; }
@@ -281,6 +282,37 @@ int main() {
     fledasty_utf8_string_free(&encoded_string);
 
     fledasty_utf8_string_free(&test_utf8_string);
+
+    FledastyString normal_test_string = { 0, 0, NULL };
+
+    fledasty_string_append(&normal_test_string, "Testing", 7);
+    printf("Append: %s\n", normal_test_string.character_string);
+    fledasty_string_insert_at_index(&normal_test_string, normal_test_string.size, "index", 5);
+    printf("Insert at index: %s\n", normal_test_string.character_string);
+    fledasty_string_insert_before_string(&normal_test_string, "nd", 2, "Hello", 5);
+    printf("Insert before: %s\n", normal_test_string.character_string);
+    fledasty_string_insert_after_string(&normal_test_string, "nd", 2, "Bye", 3);
+    printf("Insert after: %s\n", normal_test_string.character_string);
+    fledasty_string_pop(&normal_test_string);
+    printf("Pop: %s\n", normal_test_string.character_string);
+    fledasty_string_remove(&normal_test_string, "Bye", 3);
+    printf("Removed string: %s\n", normal_test_string.character_string);
+    fledasty_string_remove_range(&normal_test_string, 0, 6);
+    printf("Remove range: %s\n", normal_test_string.character_string);
+    fledasty_string_replace_string(&normal_test_string, "Hello", 5, "Goodbye", 7);
+    printf("Replace: %s\n", normal_test_string.character_string);
+
+    fledasty_string_shrink_to_fit(&normal_test_string);
+    if (fledasty_string_has_string(&normal_test_string, "bye", 3)) {
+        printf("String contains bye!\n");
+    }
+
+    fledasty_string_clear(&normal_test_string);
+    if (fledasty_string_is_empty(&normal_test_string)) {
+        printf("String is empty!\n");
+    }
+
+    fledasty_string_free(&normal_test_string);
     printf("Done\n");
     return 0;
 }
\ No newline at end of file