Since 1974, the Linux grep command has been helping people find strings in files. But sometimes grep is just too thorough. Here are several ways to tell grep to ignore different things.
The grep command searches text files looking for strings that match the search patterns you provide on the command line. The power of grep lies in its use of regular expressions. These let you describe what you’re looking for, rather than have to explicitly define it.
The birth of grep pre-dates Linux. it was developed in the early 1970s on Unix. It takes its name from the g/re/p key sequence in the ed line editor (incidentally, pronounced “ee-dee”). This stood for global, regular express search, print matching lines.
