Part of the Build a Bitcoin Node pathway. Use the guide library to follow another setup path.
A node checks the rules for itself
A Bitcoin full node receives blocks and transactions and validates them against the rules implemented by its software. It maintains a view of the chain and the coins that remain unspent. Connecting your wallet to a node you control can let that wallet use your own validated view instead of a third party's server.
Running the software does not automatically route every wallet through it. Wallet compatibility and connection settings matter. A node also needs a maintained operating system, storage, electricity and network access; running one is optional.
A node is not the same as a miner or a wallet
Mining competes to produce blocks through proof of work. A validating node checks whether a block is acceptable; it does not need to mine to do that. A wallet manages keys and constructs payments. Bitcoin Core can include wallet functionality, but a node can run without a wallet.
There is no automatic payment for simply operating a node. More addresses in a crawler's dataset do not necessarily mean more independent operators, and node counts are not votes weighted by IP address.
Full validation and pruning answer different questions
A pruned node validates the chain but discards older block files after processing them. An archival node retains those files. Pruning reduces retained disk usage; it does not remove the initial validation work or turn a node into a lightweight wallet.
Retaining old blocks is useful for serving historical data and some rescans or indexing workflows. Choose pruning if limited disk space is your main constraint and your wallet workflow supports it. Restoring or importing older wallet history can require downloading data again. A pruning target is not the total disk footprint: indexes, chainstate and other files need room too.
Public reachability is a separate choice
A node can establish outbound connections and validate without accepting inbound public connections. Router settings, firewalls, Tor, private networks and intermittent uptime can keep a functioning node out of a public clearnet crawler's reachable count.
Atlas counts a reachable node when a public address completes a Bitcoin P2P handshake from our vantage point. That observation is useful for network research but cannot establish how many full nodes exist in total. Start with the Build a Node pillar if you want to choose an installation path.
Official references
Check settings against your installed release. The Bitcoin full node guide explains operation and connectivity; Bitcoin Core downloads includes verification instructions. For sync diagnostics, consult the versioned getblockchaininfo reference and your release's built-in help.
Ready to test inbound P2P access? Check whether your Bitcoin node is reachable. To interpret what Atlas sees, explore observed Bitcoin nodes and our methodology.