Two "factors" are multiplies together to product another number (the product). So, for example, the prime factors of 10 are 2 and 5. Prime factors that, themselves, have only factors of 1 and themselves. Non-prime numbers, like 10, have prime factors. Note that 1 is a factor of all integers.
If the two factors are equal (the same), like 4*4=16, then each of them is called a "square root."
Note: a cube root is one of three equal factors of a number, for example, 2 is the cube root of 8 (that is, 2*2*2=8).
Practice:
What is the square root of 49?
What is the square root of 100?
What is the square root of 625?
Memorize the squares of the numbers from 1 to 10, or 1 to 20 -- that will be very helpful in math classes.