1. A computer-implemented method of controlling playback of digital content by a playback device, the method comprising: receiving data that includes the digital content, first data processing instructions, and second data processing instructions, the first data processing instructions being specific to the digital content and being executable by a computer language interpreter of the playback device to authenticate the second data processing instructions, the second data processing instructions being executable by the computer language interpreter of the playback device to request an access to a memory of the playback device; and executing the first data processing instructions by using the computer language interpreter, the first data processing instructions configuring the computer language interpreter to: obtain a cryptographic value of the second data processing instructions; determine an authenticity of the second data processing instructions by using the cryptographic value; based on the authenticity, performing a first operation, the first operation being selected from a first group consisting of: inhibiting playback of at least a portion of the digital content, and enabling the access by the computer language interpreter to the memory of the playback device, the access being performed by the computer language interpreter pursuant to execution of the second data processing instructions.