Trojans are malicious applications that pose themselves as legitimate software in order to trick users to install them. Once on the victim's machine, it may run any number of malicious process to steal vital information or inflict damage to other software.
HabboSteal is a phish scheme centered around Habbo Hotel. Users are sent to a fake login screen for the site that is identical to the actual service. When victim's enter their username and password, it logs them in directly to HabboHotel and stores their login credentials for the attacker.