It is the Duty of every developer to validate and make sure that all the data that users supply are valid before it gets to the database, Today I will ensure we touch both sever side and client side validation using the regular expression. "In theoretical computer science and formal language theory, a regular expression (abbreviated regex or regexp and sometimes called a rational expression) is a sequence of characters that define a search pattern, mainly for use in pattern matching with strings, or string matching, i.e. "find and replace"-like operations. The concept arose in the 1950s, when the American mathematician Stephen Kleene formalized the description of a regular language, and came into common use with the Unix text processing utilities ed, an editor, and grep (global regular expression print), a filter." - Wikipedia.

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