Introduction:
Regular expression is set of rules or predefined patterns.we can use regex for email addresses,phone numbers etc.
In php we have two sets of regular expression:
- POSFIX regex.
- PEARL style regex.
POSFIX:
POSFIX stands for Portable Operating System Interface for uniX , set of rules support by unix os.
PEARL Style Regex:
This regex structure follow the rules which use in PERL programming language.
