---
title: Software Components
description: Every Ocean network is brought to life by many interacting symbiotic software components.
---
Before reading this page, you should understand some [Ocean-specific terminology](/concepts/terminology/).
## Keeper
A computer running an EVM-compatible blockchain client
(such as [Parity Ethereum](https://www.parity.io/ethereum/))
where the associated blockchain network is running the Ocean Protocol
[keeper-contracts](https://github.com/oceanprotocol/keeper-contracts)
(smart contracts).
See also: [Run a Keeper](/setup/keeper/)
## Secret Store
A [Parity Secret Store](https://wiki.parity.io/Secret-Store): software for distributed key pair generation, distributed key storage, and threshold retrieval. It's used to store [asset](/concepts/terminology/#asset-or-data-asset) access-control keys.
There are several clients for integrating the Parity Secret Store into Ocean:
## Aquarius
Marketplaces run Aquarius to store and manage metadata about the [assets](/concepts/terminology/#asset-or-data-asset) available in their marketplace. It provides an HTTP API for interacting with an off-chain database (sometimes called "OceanDB").
### OceanDB Drivers
Aquarius supports several options for the off-chain database (OceanDB), including Elasticsearch and MongoDB. One can add support for another off-chain database by creating a new driver similar to the existing OceanDB drivers.
Note: There is also a BigchainDB driver but it hasn't been maintained.
## Brizo
Publishers run Brizo to manage interactions with marketplaces and consumers.
It interacts with the publisher's cloud and/or on-premise infrastructure.
The most basic scenario for a publisher is to provide access to the [assets](/concepts/terminology/#asset-or-data-asset) the publisher owns or manages, but [Brizo can do much more](/concepts/architecture/#brizo).
### Osmosis Drivers
Brizo supports several options for file storage, including Azure Storage, Amazon S3 and on-premise storage. One can add support for another file storage option by creating a new driver similar to one of the existing Osmosis drivers.
## Squid Libraries
Client libraries used by applications (such as Pleuston or Jupyter notebooks) to interact with Ocean components, including Keepers, Aquarius nodes, Brizo nodes, etc.
![How Squid is Used](images/ocean-squid-ecosystem.png)
## Pleuston
An example marketplace/publisher front-end for developers to explore, download, and publish [assets](/concepts/terminology/#asset-or-data-asset) in an Ocean Protocol network. Implemented using [React](https://reactjs.org/) and [squid-js](https://github.com/oceanprotocol/squid-js).
## Commons Marketplace
An online example marketplace/publisher for consumers to explore, download, and publish open data sets in the [Pacific Network](/concepts/pacific-network/). Implemented using [React](https://reactjs.org/) and [squid-js](https://github.com/oceanprotocol/squid-js).
For more information, see [the blog post about Commons Marketplace](https://blog.oceanprotocol.com/the-commons-data-marketplace-c57a44288314).