The OR Operation is also one of the functions in a digital logic circuit. It is represented by a plus (+) sign.
For example: x + y = z which is read as “x or y is equal to z”. The truth table for the OR operation is shown in the table below:
The truth table for the OR operation shows that x and y are the two inputs and z is the output. When the value of x and y both are 0 the output will be zero. When x is equal to 0 and y is equal to one, and then z is equal to 1. When the value of x is equal to 1 and y is equal to 0 then the value of z will be 1. The value of z is 1 when x or y both is 1.
Binary logic resembles binary arithmetic and the operation OR, and AND has some similarities with arithmetic addition and multiplication respectively. Although the symbols used for OR and AND operations (plus and dot) are same as those used for arithmetic variable addition and multiplication, one should know how to distinguish between a binary arithmetic variable and a logic variable. The binary arithmetic variable can consist of one or more digits, but the logic variable always consists of one digit 0 or 1.
Let us take an example to understand this.
In binary arithmetic we have 1+1 = 10, whereas in binary logic 1+1 = 1
Also See: AND Operation
Also See:: NOT Operation