Terminology - What's a Ledger in Stellar?

Question

This may sound simple, but to people (like myself) coming from Bitcoin, its not immediately clear what a "Ledger" is. Does it equate with "The blockchain" or the "block"?

The Stellar documents are quite unclear. For example:

A ledger represents the state of the Stellar universe at a given point in time. It contains the list of all the accounts and balances, all the orders in the distributed exchange, and any other data that persists.

this sounds like the Ledger is a blockchain, since it contains all the data. but later on the same page:

Every ledger has a ledger header. This header has references to the actual data within the ledger as well as a reference to the previous ledger.

so every ledger has a previous ledger? that sounds like a block.

help me out here - how should I think of Ledger? what is it?

Answer 1

It's neither the blockchain nor the block. The global ledger is close to the blockchain while the last closed ledger is the latest confirmed set of accounts, trustlines, data and offers, which is pretty much the last confirmed block of a blockchain.

Like a traditional ledger, the Stellar ledger records a list of all the balances and transactions belonging to every single account on the network. A complete copy of the global Stellar ledger is hosted on each server that runs the Stellar software. Any entity can run a Stellar server.

These servers form a decentralized Stellar network, allowing the ledger to be distributed as widely as possible. The servers sync and validate the ledger by a mechanism known as consensus.

Source: Stellar.org (Emphasis mine)