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In-Depth Information

What Is a Boolean?

Boolean is the logic used to determine whether a statement is true or false. There are four main operators used in comparing boolean variables to determine their status. They include and, not, or, and xor. An explanation of the various operators follows:

• For x and y to be true, both x and y must be true. All other cases are false.
• For not x to be true, then x must be false.
• For x or y to be true, then if either x or y are true then the statement is true. For the statement to be false both x and y must be false.
• For x xor y to be true, only one of the two variables may be true. Should both variables be true or false then the statement would be false.

Boolean expressions and variables are commonly used in computer software applications to help determine the flow of a program's logic. Boolean expressions actually came out of the field of mathematics and was developed by a gentleman from Great Britain, George Boole, who lived from 1815 to 1864. His idea was to create a kind of melding of logic, algebra, calculus, and linguistics. He saw the advantages of making binary comparisons in information systems, allowing very complex processes to be broken down into simple parts.1