There are various categories/subclass and assessment levels of Student Visas. The most generally desired Visa is the Temporary Visa( Subclass 573) Assessment level 3, which applies if   you are seeking one of either:

• Bachelor degree
• associate degree
• graduate certificate
• graduate diploma
• Masters by coursework
• Higher Education diploma
• Higher Education advanced diploma.

With this visa:

• you can study in Australia
• eligible dependant family members can accompany you to Australia
• when you have commenced your course of study in Australia, you can work up to 20 hours per week while your course is in session and unlimited hours during scheduled course breaks.
• your family members can work up to 20 hours per week provided you have commenced your course of study in Australia. If you are doing a postgraduate course, such as a Masters degree, your family members can work unlimited hours once you commence this course.
  
• your partner can study in Australia for up to three months.
  Note: If your partner wants to study for more than three months they must apply for their own student visa. The application can be made in Australia.

The Visa Application Charge is about $600