Esters are compounds formed from a reaction between an alcohol and an acid. Esters have pleasant fruity smells and are used as artificial food additives. Esters occur naturally in fruits. The natural esters give fruits their individual flavour and smell. The animation below shows the reaction between ethanol and methanoic acid.

There is a certain methodology to naming esters.

Replace the "anol" part of the alcohol with "yl"
in this case ethanol becomes ethyl

Replace the "oic" part of the acid with "oate"
in this case methanoic becomes methanoate

Placing the two names together we get

ethyl methanoate

Esters can also be formed into giant polymers. Polyester can be blow moulded into bottles and recycled to make fibres for use in carpets. Clothing made from polyester fibres are remarkably strong and resistant to creasing. The alcohol and acid monomers used in this condensation polymerisation reaction have two functional groups each and are able to to attach and grow at either end. Click to see an animation.

Experiment (ester formation)