Regex looks scary but the basics are simple. You only need to know about 10 patterns to handle most use cases.
The Essentials
. = any character. * = zero or more. + = one or more. ? = optional. \d = digit. \w = word character. ^ = start. $ = end.
Practical Patterns
Email: \w+@\w+\.\w+. Phone: \d{3}-\d{3}-\d{4}. URL: https?://\S+. IP: \d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}.
Testing
Always test regex on sample data before using in production. Use regex101.com for interactive testing with explanations.