An Electronic Travel Authority (ETA) visa is suitable if you are travelling to Australia for a short period of time. This could be to go on holiday, a business trip, or to visit family or friends. It is an electronic visa so your passport does not get stamped or labelled. It is valid for 12 months, although you can only stay in Australia for three months at a time.
Applications are made online, and the main requirement is that you come from an ETA country. ETA countries include Andorra, Austria, Belgium, Brunei, Canada, Denmark, Finland, France, Germany, Greece, Hong Kong, Iceland, Ireland, Italy, Japan, Liechtenstein, Luxembourg, Malaysia, Malta, Monaco, Netherlands, Norway, Portugal, Republic of San Marino, Singapore, South Korea, Spain, Sweden, Switzerland, UK and USA. You must also be in good health, and you can’t have served a prison sentence for longer than 12 months.