Why use deflate instead of gzip for text files served by Apache?

What advantages do either method offer for html, css and javascript files served by a LAMP server. Are there better alternatives?

How can I pre-compress files with mod_deflate in Apache 2.x?

I am serving all content through apache with Content-Encoding: zip but that compresses on the fly. A good amount of my content is static files on the disk. I want to gzip the files beforehand rather than compressing them every time they are requested.