As most of you know, when being tried for murder, there are several different categories to fall under. Sometimes I think it's unclear how murders are ranked so I'm here to clear that up!
1st Degree/Capital Murder
This is, by far, the most serious type of murder. In most states, it involves premeditation and planning or malice. Planning is deliberate if the perp make a clear decision to take the victim's life. Premeditation is when the perp thinks through the murder before it is committed. In some states, there are additional factors used to distinguish 1st degree murder. First and foremost, motive is looked at thoroughly. Another factor is the context of the murder - how it occured. Also, certain states will charge a person for 1st degree murder is more than one victim is killed at the time or if the victim's age caused them to be vulnerable. Things like sexual assault and robery coexsisting with the murders are also factors that can push a murder into the capital murder category.
This is when someone kills with malice. There's no premeditation or deliberate planning. Malice is doing a harmful act without just cause or legal excuse. So, for 2nd degree murder, you're still killing intentionally, you just didn't plan as well. This usually takes place in heat-of-the-moment, emotional situations.
Felony Murder
These murders are particularly planned or intended; while committing a felony, murder happened to take place as well. Even an accidental death will be considered murder if it takes place during the time of the felony.