From The Aquarium Wiki
Oscars (or Astronotus ocellatus) are large, territorial and commonly sold South American Cichlids. They are well loved due to their curious nature and acknowledgement of their owners, recognising the human that feeds them. Due to their popular nature they are often housed and fed incorrectly, have a read of this article if you're thinking of getting yourself an Oscar.
For more details please click on the Title name.