The rapidly increasing complexity of systems is driving the movement towards autonomic systems that are capable of managing themselves without the need for human intervention. Without autonomic technologies, many conventional systems suffer reliability degradation due to the accumulation of errors. The autonomic management techniques break the traditional reliability degradation trend. This paper comprehensively describes the roles and functions of various autonomic components, and systematically reviews past and current technologies that have been developed to address the specific areas of the autonomic computing environment. A new mechanism of model-driven autonomic management is further presented, which is more intelligent and efficient.