Logical operation on data especially in the web where we have HTML, CSS, Script in mixed form (mixed data), at the same time we need to find meaning full data with mixed nature of data is a complex operation. In order to have better performance doing so, we will have a regular expression which can help us.
What is Regular Expression?
A nice definition from Wikipedia is,
"A regular expression, regex or regexp (sometimes called a rational expression) is a sequence of characters that define a sea