whats the purpose of jquery.mobile-1.3.1.min.map in the jquery.mobile-1.3.1 distribution?

Question

When i downloaded the jquery.mobile-1.3.1 dist i see the following structure:

demos -> directory for demos of jquery-mobile
images -> directory of images 
index.html -> index for demos
jquery.mobile-1.3.1.css -> Uncompressed with Default theme
jquery.mobile-1.3.1.js -> Uncompressed
jquery.mobile-1.3.1.min.css -> Minified with Default theme
jquery.mobile-1.3.1.min.js -> Minified
jquery.mobile-1.3.1.min.map -> ?? (what it is for? is it necessary for min version?)
jquery.mobile.structure-1.3.1.css -> Uncompressed structure without a theme
jquery.mobile.structure-1.3.1.min.css -> Minified structure without a theme
jquery.mobile.theme-1.3.1.css -> Uncompressed theme for structure without theme (can be changed by another theme)
jquery.mobile.theme-1.3.1.min.css -> Minified theme for structure without theme (can be changed by another theme)

As you can see i dont know the purpose of jquery.mobile-1.3.1.min.map, what it is for? is it necessary for min version?

Answer 1

That is a source map. They are used when debugging minified JavaScript files. Since it's only for debugging purposes it's not required.

I recommend reading Introduction to JavaScript Source Maps.