The counting board is precursor of the abacus

Abacus

The abacus, also called a counting frame, is a calculating tool used primarily in parts of Asia for performing arithmetic processes. Today, abaci are often constructed as a bamboo frame with beads sliding on wires, but originally they were beans or stones moved in grooves in sand or on tablets of...

, and the earliest known form of a counting device (excluding fingers and other very simple methods). Counting boards were made of stone or wood, and the counting was done on the board with beads, or pebbles etc. Not many boards survive because of the perishable materials used in their construction. The oldest known counting board (c. 300 BC) was discovered on the Greek island of Salamis

Salamis Island

Salamis , is the largest Greek island in the Saronic Gulf, about 1 nautical mile off-coast from Piraeus and about 16 km west of Athens. The chief city, Salamina , lies in the west-facing core of the crescent on Salamis Bay, which opens into the Saronic Gulf...

 in 1899. It is thought to have been used by the Babylonians in about 300 BC and is more of a gaming board than a calculating device. It is marble, about 150 x 75 x 4.5 cm, and is in the Greek National museum in Athens

Athens

Athens , is the capital and largest city of Greece. Athens dominates the Attica region and is one of the world's oldest cities, as its recorded history spans around 3,400 years. Classical Athens was a powerful city-state...

. It has carved Greek letters and parallel grooves.
The German mathematicican Adam Ries

Adam Ries

Adam Ries was a German mathematician. He is also known by the name Adam Riese.- Life :Almost nothing is known about Ries' childhood, youth and education. It is not even possible to determine the year of his birth with certainty. The caption on the only known contemporary portrait of the...

described the use of counting broads in Rechenbuch auf Linien und Ziphren in allerlei Handthierung / geschäfften und Kaufmanschafft.