Hello, World!

Every Go file follows the same three-beat rhythm. Run it, then read it.

Run

The three beats

1. package main — every file declares its package; main marks an executable program (vs. a library)
2. import "fmt" — pull in the format package for printing
3. func main() — execution starts exactly here

Go's opinions, visible already

• No semicolons (the compiler inserts them invisibly)
• Braces required, and the opening { must sit on the same line as func main() — a different placement is a compile error
• Unused imports are errors — delete the Println lines above and run: Go refuses to compile with an unused "fmt". Dead code never accumulates.

What's next

Packages and main in depth — how Go programs are organized and why capitalization is Go's version of public/private.