A question that often arises from people intending visiting Australia on a short term basis is "Which Australian Visa do i need?"
Well the answer is dependant on what you intend to do once in Australia.
A short explanation is as follows:

The ETA Visitor/Tourist Visa-Subclass 976-Valid for 1 year.

If you are visiting friends or relatives or sightseeing and holidaying you may stay for a maximum time of 3 months in any one visit but you can enter Australia as many times as you wish during its one year validation.This is called multiple entry.You are not allowed to work in Australia under any circumstances with this ETA Visa.
Validation is for either one year or at passport expiry date whichever is sooner.

The ETA Business Entrant-Short Validity Visa-Subclass 977-Valid for 1 year.

This visa allows business people to visit Australia to conduct business such as attending conferences,meetings, training or to discuss their business in negotiations but it does not allow them to actively work in Australia. The conditions of stay are exactly the same as the Visitor/Tourist Visa.Certain other conditions also apply.
Validation is for either one year or at passport expiry date whichever is sooner.

The ETA Business Entrant-Long Validity Visa-Subclass 956

The conditions of this visa are generally the same as the Short Validity Visa  Subclass
977 but this visa is valid until your passport expiry date.

All of the above visas can be applied for online at http://www.instanttravelvisa.co.uk
Click on eligibility and if your passport is issued by one of the 33 countries shown then you can make your application. Should you have any criminal convictions against your name your visa application may be affected and your visa refused.