Glossary

Quick definitions, A to Z. Each term is explained in depth in its guide; this is the reminder card.

Blank identifier (_) — discards a value. Required when you intentionally ignore something (unused variables are errors).
Channel — Go's way for goroutines to communicate safely. Beyond these guides' scope; the Go tour covers concurrency well.
Defer — schedules a call for when the surrounding function returns. See Control Flow.
Embedding — placing one struct inside another to compose behavior. See Structs and Methods.
Error — a value (not an exception) signaling failure, always the last return value. See Error Handling.
Exported — visible outside its package: any name starting with a capital letter.
go.mod — the file marking a folder as a Go module (project).
gofmt — the official code formatter. One style, no debates.
Goroutine — a lightweight thread, started with go. Thousands are cheap; the runtime multiplexes them onto OS threads.
Interface — a set of method signatures; types satisfy it implicitly. See Interfaces.
Map — key-value lookup table. See Variables and Types.
Method — a function with a receiver, attached to a type.
Module — a Go project: a folder with a go.mod file.
Nil — Go's "nothing here" value for pointers, maps, slices, interfaces, and more.
Package — a folder of Go files compiled together; the unit of organization and privacy.
Panic — an intentional crash. For bugs, not expected failures.
Range — iterates a slice, map, or channel with for.
Receiver — the (u User) part of a method declaration, attaching it to the type.
Rune — one Unicode character ('a', '🦀').
Slice — a growable list ([]int). Always assign back the result of append.
Struct — a named bundle of fields. Behavior attaches via methods.
Unexported — visible only inside its package: any name starting with a lowercase letter.
Variadic — a function taking any number of trailing arguments (...int).
Zero value — every variable's default: 0, "", false, or nil. No uninitialized variables exist.