There are many ways the law categorizes crimes, such as felonies and misdemeanors. Another way to categorize a crime is with the label inchoate.
An inchoate offense, according to Cornell Law School, is a crime that leads to another crime. There are three basic inchoate offenses: conspiracy, solicitation and attempt.
Conspiracy
Conspiracy is the planning of a crime and can lead to you committing the crime you planned. You can face charges for both conspiracy to commit a crime and the crime itself, which is different than how charges work for the other types of inchoate offenses.
Solicitation and attempt
Solicitation means paying someone to do something illegal for you. Attempt means that you have the intention of committing a crime but fail to carry through with committing the actual crime. Attempt is the most serious inchoate offense.
Solicitation and attempt are inchoate offenses that merge into the primary charge. For example, if you face a solicitation charge for hiring someone to murder someone else but the hired person goes through with killing the person, then you will not face both solicitation charges and murder charges. The prosecutor would only charge you for solicitation.
The reason for this is that the primary crime is more serious than the inchoate offense. You will face more severe punishment and have a more serious criminal conviction if the court finds you guilty of the primary crime.
The prosecutor may choose to charge you with the inchoate offense instead of the primary offense if there is a lack of evidence or the prosecutor feels he or she could not fully prove you are guilty of the primary offense.