While working on the command line in Linux, there may arise a situation where-in the requirement is to replace tabs in a file with spaces. The task isn’t difficult if the file is small, but what if the file you’re dealing with is huge, or worse, there are hundreds of files in which you have to make this change? Worry not, there exists a command line tool that’s specifically built for this work. The tool in question is expand, and in this tutorial, we will discuss the basics of expand using some easy to understand examples.