Philosophiae Doctor - PhDIn this thesis only Binary codes are studied. Firstly, the codes overs the field GF(2) by the adjacency matrix of the complement T(n), ofthe triangular graph, are examined. It is shown that the code obtained is the full space F2 s(n/2) when n= 0 (mod 4) and the dual code of the space generated by the j-vector when n= 2(mod 4). The codes from the other two cases are less trivial: when n=1 (mod 4) the code is [(n 2), (n 2 ) - n + 1, 3] code, and when n = 3 (mod 4) it is an [(n 2), (n 2) - n, 4 ] code.South Afric
