What is a Regex?
A Regex (short for Regular Expression) is a sequence of characters that defines a search pattern. It’s used to match, find, or manipulate text based on specific rules.

How does it work?
Regex works by combining literal characters and special symbols to describe patterns in text. For example:

• \d matches any digit (0-9)
• \w matches any letter, number, or underscore
• . matches any single character
• +, *, ? specify how many times a pattern should occur

Example: the regex \d{3}-\d{2}-\d{4} matches text like 123-45-6789, which could represent a social security number format.

What is Regex used for?
Regex is widely used in programming and data processing to:

• Validate input (emails, phone numbers, passwords)
• Search for specific patterns in text
• Replace or extract parts of strings
• Parse logs, code, or data files

It’s a powerful tool because it allows complex text patterns to be described concisely, but it can be tricky to read if patterns get very long.