When your bot receives a message, Telegram sends an update object to your bot. The update contains information about the chat, the user, and of course the message itself. There are numerous other updates, too: https://core.telegram.org/bots/api#update

Message bundles are single-language stores of translation resources. They are responsible for formatting message values and attributes to strings.

Fluent Resource is a structure storing parsed localization entries.

Negotiates the languages between the list of requested locales against a list of available locales.

Type of the context object that is available inside the handlers for bot.hears.

Middleware in the form of a function.