It sounds like you want to place marks in the file.
mx places a mark named x under the cursor
y'x yanks everything between the cursor's current position and the line containing mark x.
You can use 'x to simply move the cursor to the line with your mark.
You can use `x (a back-tick) to move to the exact location of the mark.
One thing I do all the time is yank everything between the cursor and mark x into the clipboard.
You can do that like this:
"+y'x
NOTE: In some environments the clipboard buffer is represented by a * in stead of a +.
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answered 2012-11-19T03:28:48.383