The three common types of hacking are white hat, grey hat, and black hat. ·White hat hackers are computer professionals who test security on sites to find flaws and fix them before people with malicious intent can take advantage of these vulnerabilities. ·Grey hat hackers are ethical computer professionals who use their knowledge for good and bad. This could mean using their skills to expose security flaws or hacking a site to make it more secure. · Black hat hackers are the people who find vulnerabilities for personal gain or just illegally access other sites.