This video deals with numbers called indices, specifically as applied to algebra. We often call them powers, or exponents. An example is the number 35, which we read as “three to the power of five”. This means three times itself five times:
35 = 3 x 3 x 3 x 3 x 3
Here the number 5 is called the exponent or the index. The plural of index is indices.
This definition of indices, or exponents, is well demonstrated here:
This topic builds on the fundamental concepts of algebra covered in Introduction to Algebra. If you need a refresher on algebra in general, watch that video first, then come back.