Can Layer 2 technology (Lightning Network) enhance Bitcoin's practical utility?

Yes, absolutely, and it's fair to say that without technologies like the Lightning Network, Bitcoin would struggle to be truly "usable."

Let me give you an analogy, and it will become clear.

You can imagine Bitcoin's mainnet as a national vault system. Its primary mission is security, accuracy, and immutability. Every transaction is like a heavily guarded gold transport process from Vault A to Vault B. This process is extremely reliable, but its drawbacks are also obvious: it's slow, and the cost is high. If you just want to buy a bottle of water, but have to go through the entire vault transport process, wait half a day, and pay transaction fees that are more expensive than the water itself, that's clearly not practical.

This is the problem Bitcoin's mainnet faces: it's excellent for large-value storage and transfers where speed isn't the primary concern (like transporting gold bars), but it's not suitable for everyday small payments (like buying groceries with loose change).

The Lightning Network, on the other hand, is like building an efficient "e-wallet/bank card" system on top of this vault system.

Here's how it works: You and a coffee shop you frequent can first agree on the vault system (Bitcoin mainnet): "We're going to transfer small amounts of money back and forth, let's open a dedicated account." So, each of you deposits a small amount of money into this "shared account."

From then on, when you buy coffee every day, you no longer need to go through the vault transport process. You just need to make a note in the ledger of this shared account: "John Doe paid for one coffee at the coffee shop." This accounting process is almost instantaneous, and the fees are extremely low, almost negligible. You can buy one cup today, two cups tomorrow, make countless transactions back and forth, all very quickly and cheaply.

Until one day, either you or the coffee shop owner decides: "Okay, we're not trading for now, let's settle the bill." At this point, the system calculates the final result (e.g., how much you spent in total, how much money is left), and then this final result is recorded, once and for all, onto that impenetrable vault system (Bitcoin mainnet).

You see, through this method, countless small, high-frequency transactions are easily resolved "off-chain" within the Lightning Network, without clogging up the mainnet's "gold transport channel."

To summarize, what does the Lightning Network bring to Bitcoin?

1. Speed: Transactions are almost instantaneous, no longer requiring a 10-minute wait or even longer.
2. Low Cost: Transaction fees are extremely low, making small payments like buying a coffee or tipping an article possible.
3. Scalability: Greatly alleviates pressure on the mainnet, allowing the entire Bitcoin network to handle more transactions.

So, the Bitcoin mainnet continues to play its role as "digital gold," responsible for the secure storage of large assets. The Lightning Network, however, gives it the capability of "digital cash," allowing it to truly enter daily life for spending and payments. This significantly enhances Bitcoin's practical utility.