Exponent is the number of times a number is multiplied by itself. Exponents are written as xy; where x is the number and y is the exponent or power.
Example: 2 * 2 * 2 * 2 * 2 = 25
Learn more about exponents.
The square of a number is that number raised to a power of 2. In other words when we multiply a number by itself we get the square of the number. Example 2 * 2 = 4
The square root of a number x is the the value which when multiplied by itself gives the number x. In the above example 2 is the square root of 4.
Learn about squares and square roots and different ways to calculate them.