C file input/output

When you want to read or write information from a file in C, you need to use special commands called file input/output (or file I/O for short). These commands help your program talk to files like you talk to your friends.

Imagine you have a toy box filled with toys, and you want to see what toys are inside the box. The toy box is like a file, and the toys inside are like the information you want to read or write. First you need to open the toy box (file) with a specific command called `fopen()`. Then you can use other commands like `fread()` and `fwrite()` to read or write the information inside the file (toys in the toy box).

But be careful, just like you need to close the toy box when you're done playing, you also need to close the file when you're done reading or writing information in C. This is done with the `fclose()` command. If you don't close the file properly, you might lose some of your information (toys) or even break your program (or the toy box!).

So, to sum it up: file input/output in C helps your program read and write information from files, like opening a toy box to see what's inside. You use commands like `fopen()`, `fread()`, `fwrite()` and `fclose()` to interact with files. If you don't close the file properly, bad things might happen!