A regular expression is a concise and flexible means for matching strings of text, such as particular characters, words, or patterns of characters. A common abbreviation for this is “RegEx”.
RegEx are widely used in cybersecurity either running on hardware like Next Generation Firewalls or Smart Network Interface Cards or as a software application running on premise servers or in the cloud and their application in big data analytics and computational storage is increasing. You can think of regular expressions as wildcard lookups but with a greater number of wildcard types. With wildcards you can simply look up all the files in a directory with the filetype of Powerpoint *.ppt or *.pdf or *.txt or *.doc. Regular expressions can do this too. The equivalent regular expression for a textfile is .*\.tx
You can create more powerful matching formats and notation to search for all the email addresses, website addresses, zip codes, addresses, phone numbers, and many more. Typically you can do more in one line of RegEx code than what would take many lines of code to do with string matching.