The usual case R, in addition to being array-based, can also be table-based: it has a table class in the base language, data.frame. This is great, because a lot of data comes in table form.
Here are some simple examples:
twocols <- data.frame( a = rep(1:3, 4), b = rep(1:2, 6) ) twocols ## a b ## 1 1 1 ## 2 2 2 ## 3 3 1 ## 4 1 2 ## 5 2 1 ## 6 3 2 ## 7 1 1 ## 8 2 2 ## 9 3 1 ## 10 1 2 ## 11 2 1 ## 12 3 2 onecol <- data.