Category: C#

Work with immutable System.String values.

Use Contains, Split, Replace, Trim, and comparison helpers.

Build strings with $”Hello {name}” interpolation.

Mutably build large strings efficiently with StringBuilder.

Define classes and create instances that encapsulate state and behavior.

Write recursive methods with clear base cases.

Store fixed-length sequences with arrays.

Use rectangular [,] arrays or jagged [][] arrays.

Organize behavior into methods with clear names and signatures.

Pass arguments by value; use ref/in/out when needed.