Digitalization of content is both a blessing and a curse. While it allows for efficient transmission and consumption, the ease of copying and sharing digital content has resulted in rampant piracy. Digital Rights Management (DRM) has emerged as a multidisciplinary measure to protect the copyright of content owners and to facilitate the consumption of digital content. In this paper, we survey the technological aspects of DRM. We present a discussion of DRM definitions, formulate a general DRM model and specify its various DRM components. We also evaluated emerging trends such as the use of P2P in DRM and DRM for personal access control, some noteworthy issues such as content reuse and granularity, as well as citing some future directions such as frequent content key upgrades.