In the fourth in his series Dann, shows us the benefits of the paste command:
The paste command merges the lines of two or more files or a file and standard in if a second file is not specified or a "-" is used in place of the second file. Consider the following two files. The first file, test1.txt contains the following lines:
The second file, test2.txt contains the following lines:
The paste command can be used to paste these two files like so:
paste test1.txt test2.txt
producing the following output:
one blue finch
Each line in test1.txt has been “pasted” to the corresponding line in test2.txt.
http://www.linuxintheshell.com/2012/04/10/episode-004-paste/ for the complete shownotes, including video.