Who is the "Impostor" and what is "Among Us"?

its like Clue...try to find out who the killer is..just digitally

Whats wrong? Do trolls not know how to use google or something?

First of all if you are not imposter then try to complete your task, and be alert then someone is following you or not if someone is following you that mean that player is imposter /killer  or you will see sometimes that a player is following you but not killing you , in that case you can guess he/she is trying to find an opening to kill you so that another player can't see that . that time you can guess that player is Suspicious , after that you can go to main hall and press emergency button and chat with other player or you can tell them in text that 'X' player is following you / you suspicious him/her . then if everyone is agreed with you then they will vote with you . 

Basically it is game like in your family member one person is killer and the killer will kill all of you but you don't know who is the killer , then you have investigate and find the killer . 

its like Clue...try to find out who the killer is..just digitally

In a nutshell

The imposter in the game Among Us is a player whose goal is to try and eliminate all the other crewmate players, all while not getting found out in the process.

Sus is a meme term for suspicious, in game as a way of saying someone is possibly up to no good

try this crash course, in learning what it is...basically it's a very popular social deduction game

https://www.youtube.com/watch?v=muqaBob6pfw

Among Us is a video game that is sort of similar to the 1982 movie "The Thing." The idea is that you and your friends play as a group of people on a space station, but one or two of them are imposters who are killing everyone else. Each round of gameplay, the imposters try to kill people or disrupt the station, while keeping their secret identity a secret, and the players have to vote at the end of each round to "space" someone who is acting suspicious - vote them off the island, so to speak, aka kill their character. If the innocent crew members can get rid of the imposters, then they win. If not, they lose. 

It's a form of "bluffing" or social deduction game like Town of Salem or Werewolf, and also similar to games like Gary's Mod or Dead by Daylight, where one player is a killer and the rest try to survive. Sort of an elaborate version of the old game "tag" or hide and seek when we were kids. 

You can watch people playing it on YouTube or Twitch, if you want to see how it works.