What is gel electrophoresis and how is it used to analyze?
The basic idea behind it, is that DNA will travel through the gel towards the positive pole and away the negative pole of the electrophoresis machine. The smaller the fragment, the further it will travel towards the positive pole, as it will go through the gel quickly. The larger fragments will travel slower towards the positive pole, and will travel less compared to the small fragments. This is how one can quickly compare size of DNA fragments, and possibly even compare between 2 or more DNA strands and find similarities.