This brief focuses on the current research on security and privacy preservation in smart grids. Along with a review of the existing works, this brief includes fundamental system models, possible frameworks, useful performance, and future research directions. It explores privacy preservation demand response with adaptive key evolution, secure and efficient Merkle tree based authentication, and fine-grained keywords comparison in the smart grid auction market. By examining the current and potential security and privacy threats, the author equips readers to understand the developing issues in smart grids. The brief is designed for researchers and professionals working with computer communication networks and smart grids. Graduate students interested in networks and communication engineering will also find the brief an essential resource.