1. Conditional, based upon time, event, or circumstances.
2. Slang, specific to junk mail advertising lotteries and sweepstakes to persuade as many duh-weebs as possible who haven't even entered a sweepstakes that they have already won: "if".
1. When you finish your chores, you may play; when it's dark, come inside.
2. You are guaranteed to win at least $250,000 when you return the winning number to us. (The fact that the recipient does not have the winning number, so he may as well go fly a kite, is not expressed.)