In Linux, uniq is an extremely useful command-line program for text processing. It aids in the examination and manipulation of text files by comparing or filtering out repeated lines that are adjacent. Whether you're dealing with a list of data or a large text document, the uniq command allows you to find and filter out duplicate lines, or even provide a count of each unique line in a file. It's important to remember that uniq only removes duplicates that are next to each other, so to get the most out of this command, data is often sorted using the sort command first.
An example of using uniq would be:
sort names.txt | uniq
In this example, names.txt is a file containing a list of names. The sort command sorts all the lines in the file, and then the uniq command removes all the duplicate lines. The resulting output would be a list of unique names from names.txt.
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