Elections
Lok Sabha and State Assembly elections are based on adult suffrage - every Indian citizen at least 18 years old (as fixed by the relevant Legislature's law), not otherwise disqualified for non-residence, unsoundness of mind, crime, or corrupt/illegal practice, is entitled to be registered as a voter.
This guarantees universal adult suffrage - every citizen 18 or older has the right to vote, regardless of property, education, gender, or other historical restrictions that many other democracies took decades or centuries to remove. India adopted this from the very start in 1950, and the voting age was later lowered from 21 to 18 by the 61st Amendment (1988).
This is why India, since its very first general election in 1951-52, has never had property or literacy-based voting restrictions of the kind many older democracies historically imposed - universal adult suffrage was built into the Constitution from day one.