+h3(#docker). Docker images
+
+Docker images referenced by the workflow must be uploaded to Arvados. This requires @docker@ to be installed and usable by the user running @arvados-cwl-runner@. If the image is not present in the local Docker instance, @arvados-cwl-runner@ will first attempt to pull the image using @docker pull@, then upload it.
+
+If there is already a Docker image in Arvados with the same name, it will use the existing image. In this case, the submitter will not use Docker.
+
+The @--match-submitter-images@ option will check the id of the image in the local Docker instance and compare it to the id of the image already in Arvados with the same name and tag. If they are different, it will choose the image matching the local image id, which will be uploaded it if necessary. This helpful for development, if you locally rebuild the image with the 'latest' tag, the @--match-submitter-images@ will ensure that the newer version is used.
+
+h3(#dependencies). Dependencies
+
+Dependencies include collections and Docker images referenced by the workflow. Dependencies are automatically uploaded by @arvados-cwl-runner@ if they are not present or need to be updated. When running a workflow, dependencies that already exist somewhere on the Arvados instance (from a previous upload) will not be uploaded or copied, regardless of the project they are located in. Sometimes this creates problems when sharing a workflow run with others. In this case, use @--copy-deps@ to indicate that you want all dependencies to be copied into the destination project (specified by @--project-uuid@).
+