Quarantine is an action taken by some antivirus scanners. When a file (such as malware, or a virus) is quarantined, the file is moved to a location on disk where it cannot be executed. Users concerned about the contents or data in the infected file should quarantine the infected file, so any important data has a chance to be recovered.
A virus or infected data file may also need to be quarantined if it cannot be removed or cleaned. In this case, the quarantine file will be moved to where it cannot infect the rest of the computer, protecting the system even though the file cannot be cleaned or deleted.