Fish (Friendly Interactive Shell)

Fish v4.0 (2025) is rewritten in Rust. It is famous for "It just works" – 90% of what you need (autosuggestions, coloring) is enabled by default.

When to Use

• Interactive Use: It is arguably the best shell for typing commands manually.
• Discoverability: Man page completions are generated automatically.

Core Concepts

Autosuggestions

Fish suggests commands as you type based on history and completions. Right arrow accepts.

Universal Variables

set -U my_var value sets a variable across all current and future shell instances instantly.