Nexus 7 - how do I recognize different file extensions (i.e. html, css, etc...)?

[JayNexus]

I got the Nexus 7 planning to use it as a device to code on the train here and there. However, it can't recognize my file types (html, css, js... also font types, ttf, eot, etc.). How do I get the drivers necessary to recognize these files?