What is compulsory voting and how does it apply to brazil

Voting is compulsory for Brazilians aged 18 to 70. Voting in Brazil is compulsory for all literate citizens over 18 and under 70, and optional for citizens who are aged 16 and 17, are older than 70 or are illiterate.

Compulsory voting is an effect of laws which require eligible citizens to register and vote in elections,