CBC is usually done on an automated machine through flow cytometry. When the lab result has flagged it as high, a manual counting of the WBC differentials will be done. That will be the absolute lymphs.
So, to put it in easier terms, auto is when it is done by the machine, absolute is when counting is done manually.
Lymphocytes are a type of white blood cell, which is a cell that's an important part of your immune system. One common infection to cause a low lymphocyte count is HIV. The difference between a “bad” chemical and a “good” one is one of dosage.