The abacus is a simple calculation accessory which receives its power from the efficient procedural programming of the human brain.
When learning abacus, it is very important to totally forget the level of rational thinking and to focus on the automatization of the elemantary number-manipulation algorithms. These algorithms become proceduralized quite fast, after which the accuracy and speed of the operations can be increased by practice.
The best users of abacus do not need the actual device at all; their procedural programming has become so strong that the human brain itself works as the mnemonic tool. Mental arithmetic techniques based on the visualization of an abacus frame are called "anzan" in Japanese, and the best "anzanists" have reached calculation speeds totally unattainable by the use of any external calculator.
It has been shown that the abacus training enhances some computational abilities of the human brain, such as concentration, visualization, memorization, observation and the speed and accuracy of information processing.
The abacus can also be a useful introduction to the procedural programming of the human brain.