Dave Saunders describes the concept of linear data structures:

As we said in the introduction, a data structure is ‘linear’ if the elements form a sequence.

That means that the data structure has a first and last element, and each element is connected to its previous and next element.

– An ‘array’

isa linear data structure; the items are stores sequentially.– A ‘graph’ is

nota linear data structure; any node can be linked to any other node in the graph – there is no fixed ‘sequence’.

Click through for several examples of linear data structures.