It’s a Christian religion (technically), however, they do not follow the nicene creed, meaning they do not believe in the trinity, whereas most other major Christian religions do. They also have a lot of doctrines that make them stand out from other churches for example:
- They do not celebrate birthdays. Their reasoning being that all birthdays recorded in the bible ended badly. There is nothing in the bible condemning them directly so this is simply doctrine.
- They do not celebrate christmas. They do not believe (correctly) that Jesus was born on Dec. 25, see also above about birthdays.
- They do not celebrate easter in the same way most Christians do.
- They don’t celebrate mothers day / fathers day / new years eve. While these are not as strictly enforced as the above, the reasoning being that they derive from some pagan holidays.
Also, apart from those oddities that have some rather concerning practices that make many people view them as cult like:
- A member of their religion who breaks their rules can be expelled with the result being no one who is still a JW can talk to them, family included.
- They do not accept blood transfusions based on a couple bible verses stating do not eat blood. But they don’t simply tell their members to refuse as a matter of doctrine, they severely misrepresented and misquote medical literature to make it seem that using blood is more risky than not.
What is it with them going about and spreading the word of Christ?
Well, they are fundamentalist, meaning they take the bible literally. So when Jesus says go preach just like he did they take it very literally. Actually other major Christian religions do too, but the big difference being that Catholics don’t go around trying to convince Protestants they are wrong and visa-versa.
JW’s actually believe that in 1914 god personally selected them out of all the religions on the earth to be his representative and spread the word on what people are really suppose to believe. They view themselves as the modern day equivalent of the biblical jews, in the sense that they are the only ones on earth god approves of.
To a JW the only sure way to be safe from the impending destruction of the earth (which is any day now! Really!) is to listen to them and be baptised as a JW. So to not preach is putting blood guilt of all the people who weren’t preached to on your head because they didn’t get a chance to decide if they want to listen to god’s true message for them (this is actually what they teach).