The results be promisin', me hearties!
All that DNA pirating paid off! Starting from the left column, that's a 100 base pair ladder (smaller fragments travel faster down the gel, so the one on the bottom is 100 bp, then 200 bp, 300 bp, etc.), complete genomic mouse DNA with PCR primers, a cDNA plasmid of just the gene of interest with primers, genomic DNA without primers, cDNA plasdmid without primers, and a sample with just the primers. As any idiot can plainly see, some cad cross-contaminated the primers and plasmids. Demons take their eyes! (Ah well - just more fodder for my Results and Discussion.)
So what are you actually looking at? Well, PCR is a handy way to take a big chunk of DNA and amplify (makes lots of copies of) just a small, specific piece of it. The really bright spots (brighter = more DNA) in the second and third columns that are just shy of 200 bp are amplified pieces of part of the mouse TRF2 gene. The weak bands at the same position in the fifth and sixth columns suggest that a little bit of primer (very small, very specific bits of DNA that get the copying started) got mixed up with the cDNA and vice versa. My technique is flawless, so I'm gonna blame whoever used the materials before me. Some jerk obviously used the same pippette for primers and DNA.
The second column (genomic DNA with primers) has additional bands because the genome is pretty freaking huge, and there are bound to be other spots where the primers can stick and thus copies can be made. Less intense bands mean fewer copies, probably because they represent sequences that weren't exact matches for the primers, and thus didn't stick as well or as often.
To learn more about genetics, PCR, or Gel Electrophoresis, consult your local library.