# Core concepts

This page explains general dimOS concepts that you'd use to build applications: modules, streams, blueprints, RPC, skills, and agents.

## Table of Contents

- [Modules](modules.md): The primary units of deployment in dimOS, modules run in parallel and are python classes.
- [Streams](sensor_streams/index.md): How modules communicate, a Pub / Sub system.
- [Blueprints](blueprints.md): a way to group modules together and define their connections to each other.
- [RPC](blueprints.md#calling-the-methods-of-other-modules): how one module can call a method on another module (arguments get serialized to JSON-like binary data).
- [Skills](blueprints.md#defining-skills): An RPC function, except it can be called by an AI agent (a tool for an AI).
- Agents: AI that has an objective, access to stream data, and is capable of calling skills as tools.