Almost all spiders are venomous. But for the most part their venom has little or no effect on humans. There are only a few types of spiders that have venom that’s considered “medically significant”, or that will have any chance of causing more than trivial pain or sickness. In Australia, those specific spiders are the Redback Spider, the Mouse Spider, and the Sydney Funnel Web. That said, no one has died of any form of spider bite in Australia since 1981.