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Skilled – Independent (Migrant) Visa (Subclass 175)
A permanent visa for people with skills in demand in the Australian labour market. Applicants are not sponsored and must pass a points test.
Skilled – Sponsored (Migrant) Visa (Subclass 176)
A permanent visa for people unable to meet the Skilled – Independent pass mark. Applicants must be either sponsored by an eligible relative living in Australia or nominated by a participating State or Territory government. Applicants must pass a points test lower than that for the Skilled – Independent visa.
Skilled – Regional Sponsored (Provisional) Visa (Subclass 475)
A three (3) year provisional visa for people who can meet the lower pass mark for this visa. Applicants must be either sponsored by an eligible relative living in a designated area of Australia or nominated by a participating state/territory government. After living for two (2) years and working for at least one (1) year in a Specified Regional Area, applicants can apply for a permanent visa.
Skilled – Recognised Graduate (Temporary) Visa (Subclass 476)
An 18 month temporary visa for graduates of recognised overseas educational institutions who have skills in demand in Australia. There is no points test for this visa.
参考资料：http://www.immi.gov.au/skilled/general-skilled-migration/visa-options-outside.htm