Most plastics are polymers, as is hair and (perhaps) bathplug chains.

• Linear Polymers (like hair - which is actually a rope of keratin fibres (which are coiled-coils of helices!)) are chains; a linked list is a polymer in a sense.
• Dendritic Polymers are like starfish. From a central hub, chains radiate outwards, branching repeatedly. The humble skoosh ball resembles a large dendritic polymer.
• Living Polymers, Block Co-Polymers, Self-Assembling Photonic Band Gap Polymers. I wouldn't worry about them.

  In summary, polymers are strings made from monomers (letters?).