• This chapter provides fundamental knowledge of different methods of productions / heat treatments of magnesium alloys and the use of various types of cast and wrought magnesium alloys. • The influences of alloy composition, microstructure and heat treatment on chemical and mechanical properties of magnesium alloys will be discussed in relation to its applications. Suranaree University of Technology Tapany Udomphol May-Aug 2007 Introduction • Found 2.8% in sea water and other forms, i.e., dolom