Deployment techniques refer to the various methods used to release software applications into production environments. Common techniques include blue-green deployment, where two identical environments are maintained, allowing for seamless switching between them during updates, and canary releases, which involve rolling out changes to a small subset of users before a full-scale launch. These techniques help minimize downtime and reduce the risk of introducing bugs. Other methods include rolling updates, where updates are gradually applied to instances, and recreate deployment, which involves stopping the old version and starting a new one. Each technique has its advantages and is chosen based on specific project needs.