paste

This will merge two files placing the text side by side in columns. There are two major options.

Options

-d'n' this will separate columns with character n

-s merge lines from one file to a single line

A simple example of paste are two files t1 and t2. t1 has the text 456 and t2 has the text test. When these are put together with paste it looks like this:

paste t1 t2

456 test

Another option is to separate the columns using a letter instead of a tab. Here is an example:

paste -d'#' t1 t2

456#test