# Technical documentation

Manuals, procedures and reference documentation are made of the same parts
everywhere: headings, steps, warnings, figures and tables. In bitmark each
part is a bit, so a support agent or a chatbot can hand over exactly the
step or the warning that answers the question.

## A procedure

```bitmark
[.h]
[#Replacing the filter]

[.note]
Switch the device off before you open it.

[.p]
•1 Open the cover.
•1 Pull out the old filter.
•1 Insert the new filter until it clicks.
```

The warning is a bit of its own type, so every app can show it the way its
users expect, and an agent never quotes the steps without it.

## Kinds of bits

Notes, hints, info, examples and danger warnings each have a bit type of
their own, many also in a collapsible form; figures and tables carry their
number and caption. The reference lists them all.

## Versions of a manual

A manual for a new model keeps the bits that did not change. An alias book
can publish the same manual under another brand, and a diff book can hold
the differences for one product variant; see
[Alias and diff books](https://docs.bitmark-association.org/concepts/alias-and-diff-books.md).