> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lerian.studio/llms.txt
> Use this file to discover all available pages before exploring further.

# What is core banking?

> A plain definition of core banking, what it manages — accounts, balances, transactions — and the five responsibilities we use to explain a modern core system.

A **core banking system** is the central platform a financial institution runs on. It manages **accounts, balances, transactions, the customers behind them, and money moving in and out** — all in one place, as a single source of truth.

Underneath all of it sits one idea that ties everything together: a trustworthy record of **who owns what** and **what moved**. The other jobs all connect to it — feeding it, moving value through it, reading it, proving it's right. That's what makes banking *banking*: money can never be quietly lost or invented. You don't need a banking background to follow along — this page just gives you the lay of the land.

## Why it's harder than it looks

***

Keeping that record right is deceptively hard, and it's the reason most of the system exists:

* **It must always balance** — money can't appear or disappear, ever.
* **It has to stay correct at scale** — millions of movements, all consistent with each other.
* **It must be provable** — to auditors and regulators, long after the fact.

## How we'll explain it: five jobs

***

There are many ways to describe a core banking platform. In this guide we use **five core responsibilities** — it's how we organize the topic for learning, not an official taxonomy.

| Job               | What it does                                                                                                            |
| ----------------- | ----------------------------------------------------------------------------------------------------------------------- |
| **Record value**  | Keeps the trustworthy record of who owns what, balanced so nothing is lost or invented. Everything else builds on this. |
| **Move value**    | Brings money in, sends it out, and transfers it between accounts.                                                       |
| **Identify**      | Registers the people and companies behind the accounts.                                                                 |
| **Report**        | Turns the raw record into statements and reports you — and regulators — can read.                                       |
| **Trace & prove** | Keeps an auditable trail of everything that happened.                                                                   |

The **Ledger** is the foundation — but it's only **one of the five**. A complete core banking system is all five working together, not a Ledger with extras bolted on. The other four build on the Ledger once value is being recorded, and capabilities like **fees** attach to it to extend it.

You adopt these pieces one at a time, not as a single machine you switch on. The upside: the same handful of ideas — accounts, balances, movements — run through all of them. Learn those once, here, and the rest of the documentation gets much easier to follow.

## In short

***

* **Core banking** is the central platform that manages accounts, balances, transactions, customers, and payments — all on one trustworthy record of who owns what and what moved.
* Keeping that record correct at scale, and provable after the fact, is the hard part — and the reason for most of what the system does.
* To learn it, we use **five responsibilities** — **record**, **move**, **identify**, **report**, and **trace & prove**. The **Ledger** is the foundation, but core banking is all five, not the Ledger alone.

<Note>
  **See it in Lerian**

  See how these jobs map to real solutions in the [Core banking vision](/en/core-banking-vision) and [Products and plugins](/en/products-and-plugins).
</Note>