# Glossary
## `byte`
In this document, a `byte` is defined as an 8-bit octet.
## `varint`
A `varint` is a variable-length-encoding of a signed or unsigned integer. See [The `varint` section of the wire format] for more information.
[The `varint` section of the wire format]: ./wire-format.md#varint-encoded-integers
## Tagged Unions
Also known in Rust as "enums". See [the Tagged Unions" section] of the Serde Data Model for more information.
[the Tagged Unions" section]: ./serde-data-model.md##enums-or-tagged-unions