What does two heads are better than one mean?

The saying "two heads are better then one" means that if you put two people together to solve a problem the result will be better then having one person do it. This is because the best ideas of one and the best ideas of another come together and build off each other, making the final product better.

The phrase "Two Heads Are Better Than One" means that if many people work together to do want they want to achieve, more will be done than just one person.
it means its better to work in a group than just by yourself

It means that having two (or more) people thinking about a problem is more likely to come up with a solution.

It means that when two people are thinking about something, its ramifications are more likely to be grasped than if only one person is thinking about it.

Consider this:

If you have a problem and you call your friend for help.

then there are 2 heads trying to solve the problem.

He/she might not be able to give you a correct answer but maybe he/she can direct you into thinking about the problem a different way.

That way you help each other and hopefully you will find the answer to the problem.

It means if two people work together on something the result is better than if only one person does it.
It means that more it's better to look at an issue with collectively than just by yourself, because you may not necessarily see all the possibilities or solutions, and that's where the other person could come in.
Two people working together to solve something is better then just one due to the laws of percentages you are twice as likely to do something.
It's the Theory of Combined Brain Power. Two people working on a problem should find twice as many possible solutions, but there are often many overlaps. It also depends on who the two people are, what their working relationship is, and whether they can actually agree on which of the possible solutions is, in fact, the correct course of action.