The base is used in algebra in connection with powers. In fact, it is called the base of a power—or the number that is used as a factor a given number of times. In the example above, 3⁴, 3 is the base. The base can either be the number used with an exponent to create a power, such as the 3 in 3⁴; or a number written as a subscript, such as with a logarithm, for example, log_ax, in which a is the base number. (See below for more information about logarithms; for more information about bases, see “Math Basics”).