The main objective of this chapter is to offer to practitioners, researchers and all interested parties a brief categorized catalog of existing lightweight symmetric primitives with their main cryptographic features, ultimate hardware performance, and existing security analysis, so they can easily compare the ciphers or choose some of them according to their needs. Certain security evaluation issues have been addressed as well. In particular, the reason behind why modern lightweight block cipher designs have in the last decade overwhelmingly dominated stream cipher design is analyzed in terms of security against tradeoff attacks. It turns out that it is possible to design stream ciphers having much smaller internal states.