# Matrix Fundamentals

A matrix is a rectangular array of data.

 In everyday language it is basically a "table." The only difference is the "cells" of the table are not seperated by lines, and the entire "table" is not enclose by lines, just brackets. The numbers are known as elements. Matrices (plural) are named using capital letters. In this page, you will learn to determine dimensions and to identify elements of matrices.

 How to Determine the Dimensions

The dimensions are listed as row x column, or n x m, where n represents the number of rows and m represents the number of columns. Be careful that you know the difference between a row and a column - and don't mix them up!

*Important Note: Rows go across, and columns go up and down.

Example #1: Look below to see how to write the dimensions of a matrix.

Make sure that you are careful not to write (4 x 2). The order matters! It must always be (row x column), not the other way around!

Example #2: Look at the additional examples below for practice.

 Identifying Elements

Matrices are named with capital letters; there elements are named with lowercase letters and subscripts. The first number of the subscript is the row, and the second number is the column (again, think row x column).

Look at the image below to learn how to identify elements within matrices.

 More Examples: