So, for example, if we're talking about humans, and let's say this allele or this gene codes for the color blue of our eyes, and this codes for some other color, then they will not be the same exact gene. This could be blue, this could be green, or this could be blue, this could be brown, and so forth. So what that means is these allele pairs do not have to code for that same identical type of protein. The proteins can be different, but those two proteins will be involved with expressing that same type of trait. So this is the difference between a locus, a gene and an allele. So a locus is basically the address point of that gene.