Excel allows you to refer to cells as just B6 or C17:D26 (for example), but ranges can also be given meaningful names like Market_Share. Here is a video to introduce named ranges and then using INDEX to access cells within a named range:

Named Ranges and INDEX

Creating graphs of data with the use of INDEX is quite useful. Here are some examples:

Single Variable Scatterplots

Histograms (using the FREQUENCY function)

XY Scatterplots