DACA is a special program announced by President Obama on June 15, 2012. It allows for some undocumented individuals, between the ages of 15 and 31 to apply for protection against deportation, and to work legally in the U.S. for a two year period.
Some people call DACA the Dream Act. The Dream Act is not a law, but only a proposed law. DACA is a program that started as an alternative to the Dream Act. DACA is not a green card or a visa, and it is not a path to citizenship. It only means that the government will not deport you for a period of two years, and will allow you to work for two years.