Syntax highlight in vim by file extension

How to add file extension syntax highlighting to vi.
Whack this in your ~/.vimrc

au BufNewFile,BufRead *.tt set filetype=perl

(source)

vim tabs and buffers basics

in vim type  ":grep -Ri search_string *"
...it executes... press enter to get back to vim
then type ":copen" to open a window with the search results in
and you can browse the matches really easily

:help grep

then if you press enter to open one of the files found,
to get back to your original file type :buffers or :ls

:tabe #[number against file] will open the original file in a new tab
:sp #[number against file] will open the original file in a new window

:buffer [number against original file] will open the original file again
and you could make the F keys load the buffers

I prefer tabs over buffers because they're more visible
in bash vim -p file1 file2 will open 2 files in two different tabs
gt and gT will cycle through the files (I have that mapped to alt+left and alt+right)
:tabe will open a file in a new tab


Thanks Phill