Halley's comet was named after a British astronomer. Edmund Halley concluded that reports of three different comets which appeared 76 years apart from one another were referring to the same comet. He died before the year of his prediction, but it appeared. Therefore, the comet was named after him.
The primary difference between Halley's Comet and other known periodic comets is that Halley is the only significant comet with so short a period; it is possible to live long enough to see it twice. Most comets have periods in excess of a normal human lifespan.
It has never hit the earth - otherwise it would have ceased to exist. It comes round in a cycle about every 75 years. Mark Twain was born in the year of Halleys' Comet, and said he would probably go out with it too. He did.
hola mi amo tahrir wuz good mami well idk the massof haleys comet but yuh wuld wanna hit me up on the boost n ill tell yuh the mass peace....(: -- I'm not entirely sure if this is precise, but Halley's Comet has about a mass of 2.2 x 10^14 kg, which is about 4.85 x 10^14 pounds.
The name of the comet seen in 1986 is Halley's Comet. You can see it every 75-76 years, and is the only short period comet that is clearly visible to the naked eye from earth, and thus the only naked-eye comet that might appear twice in a human lifetime.