This paper introduces a new class of hexi codes namely, hexi polynomial codes, hexi Rank Distance codes, hexi Maximum Rank Distance codes, hexi Goppa codes and hexi wild Goppa codes. These codes are useful to create variants of the McEliece public key cryptosystem known as the hexi McEliece public key cryptosystem and its variants; these cryptosystems are secure against attacks carried out on the existing variants of the McEliece public key cryptosystem. This newly introduced cryptosystem has better error correcting capacity and lesser time complexity making it more feasible to use. The security and possible attacks on these variants of the hexi McEliece public key cryptosystem are analysed. © 2014 NSP Natural Sciences Publishing Cor.