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# Logical disjunction

**Logical disjunction**, also called **logical alternation**, is an operation on two logical values, typically the values of two propositions, that produces a value of *false* if and only if both of its operands are false.

A logical disjunction of propositions and may be written in various ways. Among the most common are these:

A truth table for appears below:

A logical graph for is shown below:

The traversal string of this graph is The proposition may be taken as a Boolean function having the abstract type where is interpreted in such a way that means and means

A Venn diagram for indicates the region where is true by means of a distinctive color or shading. In this case the region consists of three adjacent cells, as shown below:

## Resources

## Document history

Portions of the above article were adapted from the following sources under the GNU Free Documentation License, under other applicable licenses, or by permission of the copyright holders.