Q: What are the different degrees of murder?

There are varying degrees of murder and each state defines these degrees differently.
The most serious is First Degree Murder. First degree murder is usually categorized as "deliberate". The defendant made a clear-headed decision to kill the victim. With “premeditated", the defendant actually thought about the killing before it occurred (the period for this can be very brief).

In some states they consider killings committed in specific ways to be first degree murder. These vary by state and can include killing by poison, by lying in wait, and by torture.

First Degree Felony Murder is a killing that happens during the course of the commission of a felony, even if the death is accidental, it will be considered "felony murder" by most states. But, if the killing happens during certain felonies, once again determined by state, it will be considered "first degree felony murder". The felonies most often included in this category are burglary, arson, rape, robbery, kidnapping and mayhem.

Q: What is involuntary manslaughter?
Involuntary manslaughter usually occurs in only two instances. The first is when someone is killed due to criminal negligence and the second is when someone is killed during the act of another crime, where the intent was not to cause bodily injury or death. It is often referred to as "misdemeanor manslaughter".