Banks close at 5 PM.
Wall Street closes at 4 PM.
Bitcoin does not close. Ever.
So, "What is bitcoin?" may be a better explained in bullets:
Remember, Bitcoin is many things to many people.
Bitcoin is 24x7x365
Bitcoin is global
Bitcoin is technology
Bitcoin is open-source software
Bitcoin is an internet protocol
Bitcoin is decentralized database
Bitcoin is a distributed public ledger
Bitcoin is peer-to-peer value communication
Bitcoin is a payment layer for the Internet
Bitcoin is a value transfer system
Bitcoin is a speculation platform
Bitcoin is a geopolitical hedge
Bitcoin is a fiat currency hedge
Bitcoin is electronic cash
Bitcoin is digital currency
Bitcoin is cryptocurrency
Bitcoin is an asset
Bitcoin is a commodity
Bitcoin is property
Bitcoin is a virtual good
Bitcoin is gold 2.0
Bitcoin is money
Bitcoin is mathematics
Bitcoin is innovation
Bitcoin is financial inclusion
Bitcoin is freedom
Bitcoin is ...a revolution!