Before you can do anything financially, such as receive your salary when you get a job, submit your tax return, open a sole trading business, etc.. you need a tax file number.
I always thought it would take so much work. However through my own experience it was so easy, I went to a ATO front office and the lady put me in front of a computer logged onto the internet ATO website and told me to register there. A few days later I received my TFN in the post! If I had know this I could have done it from home!
Yes, it was so easy to register for a Tax File Number, so you can do any of the following when you arrive in Australia: