What is “ship” in Urbit?


A term widely used within the Urbit ecosystem is “ship.” In this article, you will understand everything about what this means.

When using Urbit for the first time, you noticed that you need to choose between a planet or comet identity. Just a reminder, planets are scarce entities (there are about 4 billion in total) and their main purpose is to serve as an identity for people to use on the Urbit network.

Comets, on the other hand, are unlimited; anyone can create as many as they want, for free. This is useful for allowing agents like algorithmic bots to navigate Urbit while applications can easily identify what is a person and what is a robot, minimizing spam.

When you start navigating Urbit with an identity, you are creating a ship. This ship is nothing more than the complete structure that represents your identity and all Urbit files related to it.

For example, when you enter Urbit with a planet, install the Groups app, and start chatting with some people, all of this happens within your ship. In this case, it’s a planet ship. The state of your ship is saved and can be restored at any time since you have the access keys for it. As we mentioned in the article about what Urbit is, every Urbit user is a server. A ship is, therefore, your personal server.


There are 5 types of ships that can be launched in Urbit

They are:

Galaxies (8-bit addresses, 256 in total): These are the rarest and most powerful ships in the Urbit network. They are responsible for distributing software updates, organizing consensus, and allocating address space for stars. Galaxies are typically owned by organizations or individuals who invest deeply in the development and maintenance of the Urbit ecosystem.

Stars (16-bit addresses, 65,536 in total): Stars are responsible for distributing software updates to planets and routing packets between them. They also allocate address space for planets. Stars usually belong to developers, communities, or companies that provide services to the Urbit ecosystem.

Planets (32-bit addresses, 4.3 billion in total): Planets are the most common type of Urbit ship and are designed for individual users. Each planet is a unique digital identity, functioning as a personal server that runs user applications and stores their data. Planets provide a platform for communication, computing, and content sharing within the Urbit network.

Moons (64-bit addresses, 18.4 quintillion in total): Moons are child identities of planets, typically used for connected devices or automated agents that operate on behalf of a planet. As they are linked to the parent planet, moons do not have independent network resources. They are ideal for Internet of Things devices.

Comets (128-bit addresses, unlimited quantity): Comets are entities that can be created for free and without permission from any other part of the Urbit network. They are designed for temporary or low-risk use, such as experimenting with the Urbit platform or for applications that do not require a stable, long-term identity. Comets have some limitations compared to other ships. For example, they do not have the same reputation mechanisms as planets, which can cause some parts of the Urbit network to treat them with less trust. Also, their addresses are much longer and less friendly compared to planets, making them less convenient to use.

In summary, you can understand that a ship is nothing more than an abbreviation for your personal computer within Urbit, whether it’s a star, a planet, or even a comet.