Restriction enzyme: cut DNA into fragments at a sequence on the chromosome. Typically 4,6, or 8 bases. They are usually reverse palindromes. 

Recognition sites: are the locations where the restriction enzymes cut. 

Digestion fragments: are the strings between the recognition sites. They vary in length significantly, and the positions on the chromosome vary individual to individual because of mutations. 

Partial digestion: is used for genetic fingerprinting; forensics and paternity tests. Treated with restriction enzyme cutting the DNA at nearly every combination of restriction sites, then gel electrophoresis separates the fragments by weight; the resulting separation is considered a fingerprint. 

Bacterial Artificial Chromosomes (BAC): cut out a band from gel electrophoresis (to get DNA of all the same size), and modify to it work as a starting point for mapping the entire genome. 

Restriction maps: the inferred arrangements of chromosome fragments produced by doing partial digestion. 

Reverse palindrome: when the base pairs on one strand are the reverse of their complementary pair. So GATC is reverse palindromic because on the corresponding area we have CTAG.