The 457 visa is the most commonly used program for Australian or overseas employers to sponsor skilled overseas workers to work in Australia temporarily. The full title of this subclass of visa is Temporary Business (Long Stay). The title of the visa was changed to Temporary Work (Skilled) (Subclass 457) visa on the 24th November 2012.
Read more about 457 Visa: Requirements, Conversion To Permanent Residency, Restrictions On The 457 Visa, 457 Visa Update For 2012