Seeing the most suitable black occupation for the zodiac, I would like to ask what is the difference between an assassin and a killer, and what is the difference between an undercover and a spy?

1. The assassin kills people secretly, but he is an unknown killer. No matter what means are used, no matter whether it is exposed or not, just kill people.

2. Spy spies refer to the agents secretly sent by spy intelligence agencies to target countries (regions) to engage in all kinds of illegal espionage activities, mainly stealing secrets, and also refer to the citizens secretly recruited by the spy intelligence agencies of the other side to serve them. Broadly speaking, a spy refers to a person who works as a secret detective, spying on confidential information from enemies or competitors or carrying out sabotage activities to benefit the party he works for. Also known as spies and secret agents. One of the main tasks of spies is to steal information secretly or openly by illegal or legal means, and at the same time, they also carry out covert acts such as subversion, assassination, kidnapping, explosion, psychological warfare and sabotage. A person sent or hired to spy on secrets, intelligence or sabotage. Undercover only means ambush and acting as an insider.