Bitcoin Core creates a data directory when first run. On most operating systems, the wallet.dat file is hidden by default and located here: %APPDATA%\Bitcoin\ . macOS: ~/Library/Application Support/Bitcoin/ . Linux: ~/.bitcoin/ .
By default, Bitcoin Core does encrypt the wallet.dat file. This means anyone with physical or remote access to your computer could potentially steal your private keys. 3.3: Setting Up Your Wallet - GitHub Bitcoin Core Wallet.dat
At its core, wallet.dat is a database file (historically Berkeley DB) that manages the cryptographic information necessary to prove ownership of your bitcoin. It contains: Bitcoin Core creates a data directory when first run