Computers work on the base 2 numbering system, also known as the binary number system. All calculations performed by the processor on numbers are done in the base 2 number system.

------------------ 06 00000110 + 05 + 00000101 -- -------- 11 00001011 ------------------ 06 00000110 - 05 - 00000101 -- -------- 01 00000001 ------------------ 06 00000110 * 02 - 00000010 -- -------- 12 00001100 ------------------ 06 00000110 / 02 - 00000010 -- -------- 03 00000011 ------------------      This is a complex procedure of comparing voltage and switching voltage based on the results of the comparisons. The processor moves these results back to the RAM to hold until the program needs the results. When the program needs the value of that address in memory, it asks the operating system to request the processor to get the voltage of that address in memory and return the value. The operating system then gives the results to the program which either converts it to decimal for math processing or ASCII value evaluation.