Thanks for your question, there are a lot of stages that a bill—proposed law—must go through in order to become a law. These stages give members of parliament the chance to research, make speeches about, consider changes to and vote on potential laws for Australia.
During second reading debates members can explain why they support or oppose a bill. They can also raise ideas about potential changes to a bill. After the debate the members and senators vote on whether the bill should be read a second time. This vote is to decide if the majority of members agree with the overall principles of the bill and would like to proceed to the third reading.
Members and senators have the option of researching a bill through the committee process. This gives the members of parliament the chance to learn more about a bill by giving the public a chance to share their knowledge and opinions about the bill.
Consideration in Detail in the House of Representatives, and Committee of the Whole in the Senate allow members of parliament to propose and debate minor changes to the bill, then vote on those changes.
The third reading vote is to decide whether the bill in its final form (which may have been changed) should be agreed to or not. That is, would this bill make a good law for Australia.