What is a libertarian?
The word means approximately "believer in liberty". Libertarians believe in individual conscience and individual choice, and reject the use of force or fraud to compel others except in response to force or fraud. (This latter is called the "Non-Coercion Principle" and is the one thing all libertarians agree on.)
A2. What do libertarians want to do?
Help individuals take more control over their own lives. Take the state (and other self-appointed representatives of "society") out of private decisions. Abolish both halves of the welfare/warfare bureaucracy (privatizing real services) and liberate the 7/8ths of our wealth that's now soaked up by the costs of a bloated and ineffective government, to make us all richer and freer. Oppose tyranny everywhere, whether it's the obvious variety driven by greed and power-lust or the subtler, well-intentioned kinds that coerce people "for their own good" but against their wills.