Illustrated Glossary of Organic Chemistry

Linear (unbranched): A molecule or polymer with a single backbone; each monomer molecule is bonded to at most two other monomer molecules.

Octane is a linear hydrocarbon. Each carbon of the
molecular skeleton is bonded to (at most) two other carbons.

2,2-Dimethylhexane is a branched hydrocarbon.

Amylose (a component of starch) is a linear α-D-glucopyranose biopolymer.
Amylopectin (a component of starch) is a branched α-D-glucopyranose

biopolymer. Branches sprout from glucopyranose carbon 6 approximately

every 25th monomer along the glucopyranose backbone.