What are the rules for comparing strings in the C language?

In C language, string comparison is based on ASCII values. It compares each character in the strings starting from the first character until a different character is found or the end of the string is reached.

1. If the first characters of two strings are different, the relationship between the strings is determined by the size of their ASCII values. Characters with smaller ASCII values are considered smaller, and characters with larger ASCII values are considered larger.
2. If the first characters of two strings are the same, continue comparing the next character until a different character is encountered or the end of the string is reached.
3. If one of the strings has reached the end position while the other string has not, the shorter string is smaller and the longer string is larger.
4. Two strings are considered equal if they have the same characters in each corresponding position and reach the end of the strings.

It is important to note that in C language, string comparison is case-sensitive, meaning uppercase letters and lowercase letters are considered different. If you need to compare strings without considering case, you can use functions such as stricmp or strcasecmp.