The title doesn't really jump out and snag your attention, does it? What you see is what you get: Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water. It's often referred to as the Partial Test Ban Treaty (PTBT) or the Limited Test Ban Treaty (LTBT), but the official title is explicit and long for instrumental reasons.

As international law, it's important that the purpose of the treaty is clearly stated for the following reasons:

• Much clearer and more serious than something like the Boom-Boom Treaty, the title tells the reader immediately what the treaty is about. It informs us—without even having to read the body text—that nuclear weapons testing is widely banned.
• This might sound obvious, but the title makes clear exactly which treaty it is—that way, no one government representative has any questions about what they are reading, signing, or, in some cases, violating (boo).
• Since the copies of the treaty live in governmental archives from the United Nations to the Pentagon to the Kremlin and beyond, having a clear and obvious title makes it easy to find among all the other dusty documents.

Imagine being the poor clerk who is asked to find a treaty with a name that no one is able to remember. According to the United Nations Treaty Collection website:

There are currently over 560 multilateral conventions deposited with the Secretary-General, and their number keeps growing steadily as new conventions open for signature almost every year. (Source)

That's not a small number, so all the more reason to keep the title clear and simple.