The content explains how instructions are encoded in byte form, with opcodes representing each instruction’s immediate arguments. Structured control instructions have different encodings and block types are encoded in a compressed form. The content also covers reference instructions, parametric instructions, variable instructions, and table instructions, each with their specific encoding methods. The encoding of block types and structured instructions is detailed to avoid confusion in the byte codes. The content provides a comprehensive guide on how different types of instructions are represented in byte form, catering to future extensions.
https://webassembly.github.io/spec/core/binary/instructions.html