> For the complete documentation index, see [llms.txt](https://eseoghene.gitbook.io/notes-on-bitcoin-and-lightning/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://eseoghene.gitbook.io/notes-on-bitcoin-and-lightning/glossary.md).

# Glossary

* **Chaumian e-cash**: 

Chaumian e-cash is an anonymous electronic cash system created by David Chaum in 1983.

In chaumian e-cash, every coin has to come from a mint or bank to prevent double-spending.

For example, to pay Alice, Bob has to send the money to the bank who verifies the coin and then sends it to Alice.

* **Chronological:**

Chronological events are recorded in the order in which they occurred. 

* **Computationally impractical**

In Bitcoin, transactions are computationally impractical to reverse. This means that once a transaction has been added to the Bitcoin network, the computing power needed to undo it is very expensive.

* **Digital signature**

A digital signature is a way to validate that an electronic document is authentic. It works like a unique fingerprint to prove ownership of the document.

* **Node**

A computer that participates in a network.