Which quadrant is the "first quadrant"?

Question

In the coordinate plane split into four quadrants by the $x$- and $y$-axes, I learned (educated in a public school in the U.S.) that the "first quadrant" was the one with both $x$ and $y$ positive, almost always drawn to be the top right region. However, my friend (who is from the U.K.) recently told me that he learned that the first quadrant was the top left one, with $x$ negative and $y$ positive.

A quick google search brings up no such regional difference in definitions of quadrant numbers. I know it doesn't really matter for mathematics as long as there is clarity in any specific context, but out of curiousity: is it true that the first quadrant is the top left one in the U.K.?

Answer 1

I have studied Mathematics in the UK for many years, and I have never heard anyone saying that the first quadrant is the top-left region. The convention is what you say; where $x$ and $y$ are positive.

Answer 2

The enumaration of quadrants is unrelated to which side of the roads cars drive on. Wikipedia gives planetmath and MathWorld as sources for counterclockwise enumeration, starting at the "both positive" quadrant. I strongly assume that the existence of any cultural differences would have caused a discussion there.

Answer 3

Anticlockwise turnings are measured by a positive angle. That means that $\sin$, $\cos$ and $\tan$ are all positive for acute angles. In this sense top right seems sensible for first quadrant.