Bitcoin itself cannot scale to have every single financial transaction in the world be broadcast to everyone and included in the blockchain. There needs to be a secondary level of payment systems which is lighter weight and more efficient.

~ Hal Finney, 2010-12-30,
Early cypherpunk
& the second person to run Bitcoin

Think of it like this:

Bitcoin: Savings Account ~ Slower transactions for larger amounts.

Lightning: Checking Account ~ Faster transactions for smaller amounts.

Bitcoin enhanced by Lightning can be viewed as both a product (digital property) and a service (open monetary network). The ability to transfer monetary energy through time and space without government intervention or conventional banking is enormously valuable to humanity.

~ Michael Saylor, CEO
Microstrategy

Learn more about Lightning here: lopp.net/lightning-information.html