# Library Reference

A Logisim library holds a set of tools that allow you to interact with a circuit via clicking and dragging the mouse in the canvas area. Most often, a tool is intended for adding components of a particular type into a circuit; but some of the most important tools, such as the Poke Tool and the Select Tool, allow you to interact with components in other ways.

All of the tools included in Logisim's built-in libraries are documented in this reference material.

Wiring library
| Splitter
| Pin
| Probe
| Tunnel
| Pull Resistor
| Clock
| Constant
| Power/Ground
| Transistor
| Transmission Gate
| Bit Extender
Gates library
| NOT Gate
| Buffer
| AND/OR/NAND/NOR Gate
| XOR/XNOR/Odd Parity/Even Parity Gate
| Controlled Buffer/Inverter
Plexers library
| Multiplexer
| Demultiplexer
| Decoder
| Priority Encoder
| Bit Selector
Arithmetic library
| Adder
| Subtractor
| Multiplier
| Divider
| Negator
| Comparator
| Shifter
| Bit Adder
| Bit Finder
Memory library
| D/T/J-K/S-R Flip-Flop
| Register
| Counter
| Shift Register
| Random
| RAM
| ROM
Input/Output library
| Button
| Joystick
| Keyboard
| LED
| 7-Segment Display
| Hex Digit Display
| LED Matrix
| TTY
Base library
| Poke Tool
| Edit Tool
| Select Tool
| Wiring Tool
| Text Tool
| Menu Tool
| Label