Seems like it comes on by default in Ubuntu/Debian based systems for bash. Also, if you want to see the file sizes in MB, KB etc. then use 'ls -lh' command.
It's not exactly the same though. LS_COLORS only colours file types (whether it's a file, dir or symlink) and permissions, while exa appears to also set the colours based on the mime type (text, image, etc.).
Specifically, you list which extensions should get what colors. So it's more like telling ls "Color anything ending in .jpg or .gif in red", as opposed to "Color all images red".
