Zulm is the Arabic word used interchangablely for cruelty or unjust acts of exploitation, oppression, and wrong doing, whereby a person either deprives others of their rights or does not fulfill his obligations towards them.
People who commit zulm are called zalim-een.
In the Islamic context injustice or acts of cruelty are attributed to human acts and not to Allah: God does not do injustice to anyone. It is the people who do injustice to themselves.[1]