Bioinformatics is one of the newest areas of biological sciences. Since the beginning of the 1990s, many laboratories are engaged to concentrate on full genome of several species such as bacteria, yeasts, mice, plant and humans. During these collaborative efforts enormous amounts of data are collected and stored in databases. Besides gathering all these data, it is necessary to compare these nucleotide or amino acid sequences to find similarities and differences. It is not convenient to compare the sequences of several (thousand) nucleotides or amino acids sequences manually, several computational techniques were developed to approach this problem. In addition, these are less error-prone than a manual approach. Bioinformatics is all about using computing systems to store, manage, and analyze biological data and information.