Variables and types

Go is statically typed like Java and C#, not dynamically typed like Python. Variables declare with var or short declaration := inside functions.

Basic types

• int, int64, float64 — numeric types
• string — UTF-8 text, immutable
• bool — true or false
• byte (alias for uint8), rune (alias for int32) — bytes and Unicode code points

Declaration styles

var count int = 10
name := "Ada"          // short declaration, type inferred
var ratio float64 = 0.75

:= works inside functions only. Package-level variables need var with explicit types when inference is unavailable.

Important interview questions and answers

1. Q: var vs :=?
   A: var works at package or function scope; := is short declaration inside functions with type inference.
2. Q: Zero values?
   A: Uninitialized variables get zero values: 0 for numbers, "" for strings, false for bool, nil for pointers/slices/maps/channels.

Self-check

1. What is the zero value of an int?
2. Can := be used at package level?

Pitfall: := only works inside functions—package-level variables need var, unlike short declarations at module scope in some languages.