1. A method for making multi-system constraint of a specific permission in a digital right, comprising: obtaining, by an executing device, a rights object related to a content object by an executing device, wherein descriptions of a specific permission of the rights object include system constraint descriptions of a plurality of systems, a plurality of pairs of grammar elements for separating information of the plurality of systems are used for the specific permission in the rights object, each pair of grammar elements identifies information of one system, wherein the specific permission of the rights object is a play permission, or a display permission, and wherein the system constraint descriptions of a plurality of systems are target systems to which the content object is rendered; obtaining, by the executing device, corresponding system information in the executing device by the executing device according to said system constraint descriptions; comparing, by the executing device, the system information in the executing device with the system information in said system constraint descriptions; judging, by the executing device, whether the system in the system information for the executing device is a permitted system in said system constraint descriptions in the executing device; and based on the judging, determining to permit executing said specific permission for the content object when the system in the system information for the executing device is a permitted system in said system constraint descriptions in the executing device, otherwise, determining not to permit executing said specific permission for the content object.