Package encoding defines an interface for character encodings, such as Shift JIS and Windows 1252, that can convert to and from UTF-8.

Package language implements BCP 47 language tags and related functionality.

Package runes provide transforms for UTF-8 encoded text.

secure is a repository of text security related packages.

Package transform provides reader and writer wrappers that transform the bytes passing through as well as various transformations.

unicode holds packages with implementations of Unicode standards that are mostly used as building blocks for other packages in golang_org/x/text, layout engines, or are otherwise more low-level in nature.