In Australia voting is compulsory, meaning

Required

Explanation:

Compulsory means: required by law or a rule

Under the Electoral Act, the actual duty of the elector is to attend a polling place, have their name marked off the certified list, receive a ballot paper and take it to an individual voting booth, mark it, fold the ballot paper and place it in the ballot box.

Electors who fail to vote at a State election and don't provide a valid and sufficient reason for failure to vote will be fined. The penalty for first time offenders is $20 and this increases to $50 if you have previously paid a penalty or been convicted of this offence.