Full Node vs. Light Node

These two terms get used interchangeably, but they describe different levels of verification. A full node stores the entire transaction history and checks every rule itself. A light node stores very little and leans on full nodes to supply and confirm most of that data. The difference sounds small until something goes wrong, since it determines who is actually checking the rules and who is simply trusting a summary of them. Most wallet apps default to a light-node style connection without saying so, which is part of why the two get mixed up.

Full Nodes

• Complete Ledger Storage: the entire transaction history is downloaded and kept locally, which takes a growing amount of disk space over time and only increases as the network keeps operating.
• Independent Rule Checking: every transaction and block is verified using the network's own rules, without trusting another party's summary of what happened or taking a shortcut on any step.
• High Resource Cost: running one requires meaningful disk space, steady bandwidth, and near-constant uptime to stay current with the network as new blocks arrive.

Light Nodes

• Minimal Local Data: only a small subset of the ledger, such as block headers, is stored on the device instead of the full history, keeping the footprint tiny.
• Delegated Verification: transaction details are requested from full nodes rather than checked from scratch, which speeds things up but shifts the trust elsewhere.
• Low Resource Cost: they run comfortably on phones and other devices with limited storage and intermittent connectivity, with no lengthy setup required.

The actual distinction is how much each setup verifies on its own: a full node checks the network's rules directly and can catch a violation itself, while a light node depends on the full nodes it queries being honest and available. Neither setup is wrong; they just place the verification work in different places, and knowing which one a given wallet is running changes what you can actually rely on it for. For how this fits into a broader setup, see Network Monitor.