bit is a C++ library for manipulating buffers containing data fields that are not necessarily octet (byte) aligned. Binary data formats containing fields that are not octet aligned are still common. One need look no further than the IP header that is present in every packet of data transmitted on the Internet. Additionally many embedded devices and sensors still communicate via binary formats, and it was for the latter (robotic sensors) that this library was initially developed.

The bit library allows data formats to be specified at run-time through class methods or loaded from XML files at run-time (including any combinations thereof).

A companion library, bitgtkmm, provides a set of Gtkmm widgets for display of bit buffer representations.