WebAssembly (abbreviated Wasm) is a binary instruction format for a stack-based virtual machine. Wasm is designed as a portable compilation target for programming languages, enabling deployment on the web for client and server applications. (Source:

Here is a list to summarize the preceding information:

  • Wasm is a new language that officially became the fourth language of the web, after HyperText Markup Language (HTML), Cascading Style Sheets (CSS), and JavaScript. Source:
  • Wasm is a binary format. It does not aim to be human-readable.
  • Wasm is so low-level that it brings performance improvements compared to high-level languages such as JavaScript.
  • Go code can be compiled in the Wasm binary format.