Answer:
The word binary means composed of two. Binary numbers are
numbers in base two. They are written with two digits 0 and
1 using groupings of two, four,(two twos), eight (two fours),
etc.
For example 1101_{two} stands for 1 eight, 1 four, 0 twos and
1 unit, which is 13 in base ten
Computers use binary
numbers. In an electric circuit, numbers can be represented by a
current flowing (1)or not flowing (0).
When
writing binary numbers you will need to signify that the number
is binary.
For
example take the value 101, as it is written it would be hard
to work out whether it is a binary or decimal (denary) value,
to get around this problem it is common to denote the base
to which the number belongs by writing the base value with
the number, for example:
101_{2 } 2 is a binary number and 10110 is a decimal
(denary) value.
One other thing about binary numbers is that it is common
to signify a negative binary value by placing a 1 (one) at
the left hand side (most significant bit) of the value, this
is called a sign bit, we will discuss this in more detail
in the next part of the tutorial.
