Definition of Decimal Number System: The decimal number system is the base-10 number system. It uses the ten digits, from 0 to 9.
The decimal numbers are the most widely used in daily life all over the world.
Base-7 (aka septenary) number system uses seven symbols to code information. Most commonly, these symbols are, 0, 1, 2, 3, 4, 5 and 6.