The G0 experiment at Jefferson Laboratory measured the parity violating asymmetry in the cross section for polarized electrons scattered at backward angles off liquid hydrogen and deuterium. Measurements were made at two momentum transfers: 0.23 and 0.62 (GeV/c)2. Combined with forward angle measurements on a hydrogen target the contribution of strange quarks to the proton's charge and magnetization are determined. Final results will be shown and complete decomposition of the nucleon electromagnetic form factors to the up, down and strange quark contributions is obtained and will be presented.