In dna sequence analysis, it is quite common to obtain two sequences like "acgta" and "actgac" and attempt to understand how 'similar' they are.

DNA is made of nucleotides that binds together forming as a DNA sequence which dictates an organism's characteristics and features. Moreover, these nucleotides are considered in two forms; the purine (AG) and pyramidine (CTU).

Now similarities between two DNA sequences can be obtained through observance of their 3' and 5' tails.