What is difference between Continuous Delivery and Continuous Deployment?

Both encapsulate the same process of deploying the changes which were compiled and/or tested in the CI pipelines.

The difference between the two is that Continuous Delivery isn't fully automated process as opposed to Continuous Deployment where every change that is tested in the process is eventually deployed to production. In continuous delivery someone is either approving the deployment process or the deployment process is based on constraints and conditions (like time constraint of deploying every week/month/...)