Understanding build agents
To build and deploy your code using Azure Pipelines, you need at least one agent. An agent is a service that runs the jobs defined in your pipeline. The execution of these jobs can occur directly on the agent's host machine or in containers.
When defining agents for your pipeline, you have essentially two types of possible agents:
- Microsoft-hosted agents: This is a service totally managed by Microsoft and it's cleared on every execution of the pipeline (on each pipeline execution, you have a fresh new environment).
- Self-hosted agents: This is a service that you need to set up and manage by yourself. This can be a custom virtual machine on Azure or a custom on-premise machine inside your infrastructure. In a self-hosted agent, you can install all the software you need for your builds, and this is persisted on every pipeline execution. A self-hosted agent can be on Windows, Linux, macOS, or in a Docker container.
