Comments in C programming are used to add notes and explanations to the code that are not executed by the compiler. They can be used to document the code and make it more readable for other developers or for future reference.

There are two types of comments in C programming: single-line comments and multi-line comments.

Single-line comments start with two forward slashes (//) and continue until the end of the line. Anything written after // is ignored by the compiler. Here is an example of a single-line comment:

int age; // declare a variable to store the age

Multi-line comments start with /* and end with */. Anything written between /* and */ is ignored by the compiler, even if it spans multiple lines. Here is an example of a multi-line comment:

/*
This is a multi-line comment that spans multiple lines.
It can be used to add more detailed explanations to the code.
*/
int num; // declare a variable to store a number

It is important to note that comments should be used judiciously and only when necessary. Too many comments can make the code difficult to read and maintain. Comments should be used to explain complex or non-obvious parts of the code or to document any assumptions or limitations of the code.