You have already spent time this year understanding variables. There are two kinds of variables: Numeric and String. So far in our course we have used a variable to represent a single unique item.

One way of visualizing variables is that they are a mailbox. Each mailbox has a name (the variable name) and has information which is stored in the box.

name1$ name2$ a$ speed time x

George

Armando

1000

Note that a$ is a string variable and contains string information even though it contains a number. That number could not be used for calculation.

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Variables can contain different values. This is the same concept that you learned in Algebra. What is different in programming is that when we create a variable we are creating a place in memory to store the value. We are creating the mailbox.

The difference between arrays and variables is that arrays are lists of variables. For example we may have a number of names that we want to have in a list. We could visualize a single dimensioned array this way.

Name$( )

Frank

Rudy

Muraad

Lisa

Elmira

Definitions:

Numeric Variable: Numeric variables are used for storing numbers (numbers with which we want to do calculations.) If we need to add or subtract or use a variable in a formula we need for that variable to be numeric.

String variables are used for storing alpha-numeric information. Alpha-numeric information contains numbers (not used in calculations), letters and symbols.

Single-Dimension array: A Single-Dimension array has only a single column of related information.

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