How to undo and redo changes in vi/vim editor?

Question

I have a large file which has "some string"so many times, i want it to be replaced with "other string" at all places, using vi or vim editor?
Is there any way to do that?

Answer 1

You can use u for undo and ctrl+r for redo, you can also go through this link to get all available undo and redo commands...
http://vimdoc.sourceforge.net/htmldoc/undo.html