What are bitcoin layer 2 networks?
Could you elaborate on what Bitcoin Layer 2 networks are? I've heard about the scalability challenges facing Bitcoin's main network, and I'm curious to know how Layer 2 solutions aim to address these issues. Are Layer 2 networks separate blockchains? Do they work alongside the main Bitcoin blockchain? What are some of the key technologies used in Layer 2 solutions? And finally, how do they enhance the overall performance and scalability of the Bitcoin network? I'd appreciate a concise yet comprehensive explanation of the concept and its potential implications.