Character Sets [abc]

Character sets let you match any one character from a group of characters.

Basic Syntax

Square brackets [abc] match any single character inside them.

The pattern [aeiou] matches any vowel - each vowel is highlighted individually.

How Sets Work

[abc] means "match a OR b OR c" - exactly one character.

Combining with Literals

You can use character sets as part of larger patterns:

Multiple Characters in Patterns

Starting Words

Practice Playground

Try:

• [bcfm]at - matches bat, cat, fat, mat
• [aeiou][aeiou] - two vowels
• [A-Z] - (sneak peek!) capital letters

Key Takeaways

• [abc] matches any ONE character from the set
• Sets are case-sensitive by default
• Combine sets with literal characters for flexible patterns
• Order inside brackets doesn't matter: [abc] = [cba]