The **string.h** library is a library available in [[C language|C]] that defines a series of functions to deal with strings. # Library functions |unction Name|Function Description| |---|---| |[strlen()](https://www.geeksforgeeks.org/strlen-function-in-c/)|Returns the length of the string.| |[strcpy()](https://www.geeksforgeeks.org/strcpy-in-c-cpp/)|Copy one string to another.| |strncpy()|Copy first n characters from one string to another.| |[strcat()](https://www.geeksforgeeks.org/strcat-function-in-c-c-with-example/)|Concatenates two strings.| |[strncat()](https://www.geeksforgeeks.org/strncat-function-in-c-cpp/)|Concatenates first n characters of one string to another.| |[strcmp()](https://www.geeksforgeeks.org/strcmp-in-c-cpp/)|Compare two strings.| |strncmp()|Compares first n characters of two strings.| |strchr()|Find the first occurrence of the given character in the string.| |strrchr()|Finds the last occurrence of the given characters in the string.| |[strstr()](https://www.geeksforgeeks.org/strstr-in-ccpp/)|Find the given substring in the string.| |[strcspn()](https://www.geeksforgeeks.org/strcspn-in-c/)|Returns the span of the source string not containing any character of the given string.| |[strspn()](https://www.geeksforgeeks.org/strspn-function-c/)|Returns the span of the source string containing only the characters of the given string.| |[strpbrk()](https://www.geeksforgeeks.org/strpbrk-in-c/)|Finds the first occurrence of any of the characters of the given string in the source string.| |strtok()|Split the given string into tokens based on some character as a delimiter.| |strcoll()|Compares two strings that are passed.| |[memset()](https://www.geeksforgeeks.org/memset-c-example/)|Initialize a block of memory with the given character.| |memcmp()|Compares two blocks of memory.| |[memcpy()](https://www.geeksforgeeks.org/memcpy-in-cc/)|Copy two blocks of memory.| |[memmove()](https://www.geeksforgeeks.org/memmove-in-cc/)|Moves two blocks of memory.| |memchr()|Finds the given character in the block of memory.| **:: Reference ::** [C Library - <string.h> - GeeksforGeeks](https://www.geeksforgeeks.org/c-library-string-h/) **:: Reference ::** [cplusplus.com/reference/cstring/](https://cplusplus.com/reference/cstring/)