Jealousy is the uncomfortable feeling you get when you worry about losing something important to you, or when you want something someone else has. These are actually two different kinds of jealousy, and understanding the difference helps.

The first kind happens when you feel threatened. If your best friend starts spending lots of time with a new kid at school, you might feel jealous, worrying that you'll lose your special friendship. This jealousy comes from fear: fear of being replaced, forgotten, or left out. It's that tight, anxious feeling in your chest when something you care about seems at risk.

The second kind is what many people call envy, though jealousy gets used this way too. This is when you want what someone else has: their new bike, their talent at drawing, their seemingly perfect family. You might feel jealous when a classmate wins an award you wanted, or when your sister gets praised for something you wish you could do.

Jealousy can make people act in ways they later regret: saying mean things, excluding others, or giving up on friendships. The feeling itself is normal. Everyone experiences it. What matters is recognizing jealousy when it appears and not letting it control your choices. Sometimes jealousy signals that something matters to you, which can be useful information.