Grep is one of the important command that you should learn thoroughly. You know now what is grep and how to use it to search text files with matching patterns in GNU/Linux.

Is grep useful?

The grep command provides access to the grep utility, a powerful file processing tool used to find patterns in text files. It has many practical use cases and is certainly one of the most used Linux commands.

Why is grep so good?

GNU grep uses raw Unix input system calls and avoids copying data after reading it. Moreover, GNU grep AVOIDS BREAKING THE INPUT INTO LINES. Looking for newlines would slow grep down by a factor of several times, because to find the newlines it would have to look at every byte!