I know some elementary chemistry and biology. I also think I know what a gene is (it's a sequence of DNA which encodes a particular protein). I also know that on a chromosome there are sections of DNA which are kind of junk and do nothing. But being armed with this information, doesn't seem enough for me to understand what it means to "map the human genome".
a. It tells me the entire sequences of nucleotides that make up a particular human's chromosomes (it could not possibly do this for humans in general because of course the sequence is different from one human to another).
b. It tells me the entire sequences of nucleotides that make up a human's chromosomes... with some annotations along the lines of "at this point in the molecule, we could optionally have nucleotides A, B or C".
It tells me the start and stop points for each of the genes along the chromosome.
It tells me the function of every gene.
Something completely different!