# Review of ND-Arrays#

Vectors and matrices are just special cases of a more general data structure: arrays (or sometimes, ND-arrays).

Everything we learned about vectors and matrices can be generalized in a relatively straightforward manner to arrays with more than two dimensions (mostly just by including more entries between our square brackets when subsetting).

We can often do mathematical operations with arrays of different shapes and even arrays with different numbers of dimensions. The way this works is governed by the rules of

*broadcasting*.