Spear phishing is a variation of phishing. The cybercriminal upfront tries to get as much information as possible about his victim. So, there is much of work, before he is doing his phishing attack, like he spies out his victim. He doesn’t send out a mass of phishing emails, he only is interested in one target. Most of the times this are companies, heads of companies or rich people. The more personal information he has about his victim, the better he can attack his victim. More about spear phishing you can read here.