Abacus is an ancient calculating device having its roots in Asia since ages. Abacus in today’s time is made of wood, metal or plastic rectangular frame with freely sliding 5 beads over vertical rods. These beads are parted by a fixed horizontal bar where 1 bead over the vertical bar is placed above the fixed horizontal bar and the remaining 4 beads below the fixed horizontal bar. The beads above the fixed horizontal bar represent number 5 whereas other each of the 4 beads below represent number 1.
Any bead which moves towards the fixed horizontal bar gains value and when it moves away from the fixed horizontal bar looses value, which can be interpreted as 1 bead below the fixed horizontal bar moving towards the fixed horizontal bar means 1 on abacus and 4 beads below the fixed horizontal bar moving towards the fixed horizontal bar means 4 and so as the case with 1 bead above the fixed horizontal bar moving towards the fixed horizontal bar means 5. Moving away from the fixed horizontal bar is -1, -4 or -5 as the number of beads may be. Vertical rods on Abacus are used to represent the place value of number. If the centre rod of Abacus is the place of One's or Unit, the immediate next rod to the left is the place of Ten's and the immediate next rod to the left of Ten's is Hundred's and so on and so forth for Thousand, 100 Thousand, Million's etc. Learning the skills to operate Abacus can easily enable a person to perform Arithmetic Operations of Addition, Subtraction, Multiplication, Division, Square Roots, Cube Roots etc. with ease after practising the methods. In today’s time children love learning this tool and through guided Abacus Training they even can imagine abacus in their photographic mental ability to perform rigid calculations even faster than anyone attempting it on a calculator or computer.
This ancient tool of calculation has now become a Supplementary Education to strengthen children's skills for Fast and Accurate Math ability with enhancing and polishing the brain functions like Concentration, Focus, Listening, Analysing, Comprehending, Imagination, Retention, Memory, Perseverance, Creative Intelligence etc. So the modern definition of abacus is changed to, “A math tool for brain exercise".