Layer 2 (L2)
Layer 2 (L2) is a network that runs on top of a main blockchain, Layer 1. It handles lots of activity on its own and sends a compressed result to the base chain. The goal is simple: cheaper and faster transfers.
L2 security leans heavily on the base chain, but every L2 has its own rules and its own risks. Read how a specific network works before you move money there.
A transfer on the base chain is expensive at peak time. The same transfer inside an L2 costs noticeably less. But to get into an L2 you need a bridge, which is a separate transaction with its own fee and its own risk.
What not to do
Do not use a bridge from a chat link. Before sending, check that the exchange or wallet on the other side supports this exact network: a wrong network can cost you the whole amount. Bridges are sometimes hacked, so do not move more through them than you can afford to lose.