Vim is my editor of choice, but I would never consider myself an expert. So when I wanted to copy text from one text file to another in vim, I was challenged. Although I was frustrated for a brief moment, I remembered uncle google and he helped me with my conundrum. So here is how you cut and paste a section of text from one text file to another using vim.
First open your first text file in vim. Scroll down to the first line of the block of text you wish to copy and press "ma" (that is m followed by a, without the quotation marks). "m" marks the beginning of your block. The "a" makes the assignment of copying the text to buffer "a".
Now scroll to the end of the block of text you wish to copy and press "y'a" (again without the quotes). The "y" yanks the text block. The single quote in the middle, I guess designates the end of the block and "a" again identifies the buffer being used.
Next open the second text file by typing ":split filename.txt" (Remember no quotes). This will open the second text file in a split vim session window. Scroll to the line where you would like the text pasted and press "p" (You should know, don't include the quotes). This will paste the block of text on the line below the current cursor position. Save and your done.
Please leave comments with other examples of cutting and pasting in vim.