Picotux is the smallest computer

Computer

A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...

 running Linux

Linux

Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

 in the world. There are several different kinds of picotux available, but the main one is the picotux 100. It is 35 mm × 19 mm × 19 mm and just barely larger than an 8P8C modular connector. Two communication interfaces are provided, 10/100 Mbit/s half/full duplex Ethernet

Ethernet

Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....

 and a serial port with up to 230,400 bit/s. Five additional lines can be used for either general input/output or serial handshaking.

The picotux 100 operates a 55 MHz 32-bit

32-bit

The range of integer values that can be stored in 32 bits is 0 through 4,294,967,295. Hence, a processor with 32-bit memory addresses can directly access 4 GB of byte-addressable memory....

 ARM7 Netsilicon NS7520 processor

Central processing unit

The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...

, with 2 MB of Flash Memory

Flash memory

Flash memory is a non-volatile computer storage chip that can be electrically erased and reprogrammed. It was developed from EEPROM and must be erased in fairly large blocks before these can be rewritten with new data...

 (750 KB of which contains the OS) and 8 MB SDRAM

SDRAM

Synchronous dynamic random access memory is dynamic random access memory that is synchronized with the system bus. Classic DRAM has an asynchronous interface, which means that it responds as quickly as possible to changes in control inputs...

 Memory. The operating system

Operating system

An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

 is μClinux 2.4.27 Big Endian. BusyBox

BusyBox

BusyBox provides several stripped-down Unix tools in a single executable. It runs in a variety of POSIX environments such as Linux, Android, FreeBSD and others, such as proprietary kernels, although many of the tools it provides are designed to work with interfaces provided by the Linux kernel. It...

 1.0 is used as main shell

Unix shell

A Unix shell is a command-line interpreter or shell that provides a traditional user interface for the Unix operating system and for Unix-like systems...

. The picotux system runs at 250 mA

Ampere

The ampere , often shortened to amp, is the SI unit of electric current and is one of the seven SI base units. It is named after André-Marie Ampère , French mathematician and physicist, considered the father of electrodynamics...

 only and 3.3 V

Volt

The volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the...

+/- 5%.