Some shortcuts for search/replace/delete in vi:
Search for a string: /<string>
Search for string in current cursor position: *
Repeat search: n[next]/N[previous]
Highlight search: :set hlsearch
Replace every occurrence in file: :%s/old/new/g
Delete every line matching a pattern: :g/pattern/d
Delete every line not matching a pattern: :v/pattern/d
