BARK (Binär Aritmetisk Relä-Kalkylator, Swedish for "Binary Arithmetic Relay Calculator") was an early electromechanical computer. BARK was built using standard phone relays, implementing a 32-bit binary machine. It could perform addition in 150 ms and multiplication in 250 ms. It had a memory with 50 registers and 100 constants. It was later expanded to double the memory. Howard Aiken stated in reference to BARK "This is the first computer I have seen outside Harvard that actually works."

BARK was developed by Matematikmaskinnämnden (Swedish Board for Computing Machinery) a few years before BESK. The machine was built with 8000 standard phone relays, 80 km of cable and with 175 000 soldering points. It was completed in February 1950 at a cost of 400 000 Swedish kronor, became operational on April 28 1950, and was taken offline on September 22, 1954. The engineers on the team led by Conny Palm were Harry Freese, Gösta Neovius, Olle Karlqvist, Carl-Erik Fröberg, G. Kellberg, Björn Lind, Arne Lindberger, P. Petersson and Madeline Wallmark.