The alternative to using graphics is to summarize your data in tabular form. Broadly speaking, if you want to convey detail use a table, and if you want to show effects then use graphics. You are more likely to want to use a table to summarize data when your explanatory variables are categorical (such as people's names, or different commodities) than when they are continuous (in which case a scatterplot is likely to be more informative; see p. 189).
There are two very important functions that you need to distinguish:
6.1 Tables of counts
The table function is perhaps the most useful of all the simple vector functions, because it does so much work behind the scenes. We have a vector of objects (they could be numbers or character strings) and we want to know how many of each is present in the vector. Here are 1000 integers from a Poisson distribution with mean 0.6:
We want to count up all of the zeros, ones, twos, and so on. A big task, but here is the table function in action:
0 1 2 3 4 5
539 325 110 24 1 1
There were 539 zeros, 325 ones, 110 twos, 24 threes, 1 four, 1 five and nothing larger than 5. That is a lot of work (imagine tallying them for yourself). The function works for characters as well as for numbers, and for multiple classifying variables: