Post edited 1:15 pm - 05/11/2009 by Rook

few/fewer/less/lesser indicate that the quantity of something is small.

Use few and fewer with countable nouns:

I have a few things to tell you.
There were fewer voters in the evening than in the morning.

Use less and lesser with uncountable nouns:

I'd prefer less milk in my tea please.
You'll have to choose between the lesser of the two evils.

As seen above,
fewer and lesser are used to indicate that one thing is of a small quantity relative to another thing.
few and less are used when we want to say that a particular thing is of a small quantity even in absolute terms. For example:

Most of my friends live in Kerala. A few of my friends live in Karnataka.
Most of my friends live in Kannur and Kochi, but fewer live in Kannur than in Kochi.

Important: The phrase "quite a few" does NOT indicate a small quantity. It actually means "a large number of." For example:
Quite a few people had gathered to hear the politician speak.

Also note that "lesser" is rarely used to compare two quantities because "less" can perform the same function. "Lesser" is sometimes used to talk about human qualities like evil, valor, intelligence etc.

So use "less" even when you are explicitly comparing two things:
She's less interested in the job than her friend is.
I have less money than you do. [note that money and time are treated as uncountables]
Today's meeting is less crucial than tomorrow's.