It is a perfect 90°, which is often shown by a small square drawn in between the two lines An obtuse angle is an angle that is bigger than 90° degrees, but doesn’t reach a straight line at 180°.

One that I hear a lot is that you must never put a 90-degree angle on a trace ... when you find a board with 90-degree traces. Do square traces actually matter? The short answer is no, but ...