**Q: **Is diameter also called the diameter? ¶

**A: **Yes.

**Q: **Is diameter an important global Riemannian invariant? ¶

**A: **Yes.

**Q: **Is diameter the same because all such pairs of parallel tangent lines have the same distance? ¶

**A: **Yes.

**Q: **Is diameter called the major axis? ¶

**A: **Yes.

**Q: **Is diameter defined to be the largest distance that can be formed between two opposite parallel lines tangent to its boundary? ¶

**A: **Yes, and the width is often defined to be the smallest such distance.