WebAssembly Fundamentals Vocabulary

Vocabulary Reference

.wasm binary

The compact binary encoding of a WebAssembly module — a portable, validated file that browsers and runtimes can load and execute.

linear memory

A contiguous, resizable byte array that a WASM module uses for heap storage. Both the WASM module and JavaScript can read and write the same memory buffer.

table

A typed array of references (typically function references) inside a WASM module, used to implement indirect calls and function pointers.

import / export

The module boundary: imports are values or functions the host must provide; exports are functions or memory the host can call or access.

host function

A function implemented by the host environment (browser JS, WASI runtime) and passed into the WASM module via its import object.

compiled from Rust/C++/Go

WASM is typically produced by compiling high-level languages (Rust via wasm-pack, C/C++ via Emscripten, Go via GOOS=js) to the .wasm binary target.