What is functions.php file in WordPress?

What is functions.php File in WordPress? A themehas many functions, like how many thumbnails to be generated for each image, how many sidebars the layout should have, etc. Each required function is to be registered inside a file called functions.php. This is a controller file of your theme to produce the needed outputs.
For More Information Please Refer:
https://www.webnots.com/how-to-edit-functions-php-file-and-add-new-functions-in-wordpress/
You May Also Like to Read: