Ansible blocks are a way to logically group and split tasks in Ansible playbooks. They help with organization, conditional execution, debugging, error recovery, and cleanup situations. Blocks can be used for organizing multiple tasks in a common set, handling errors or failures in tasks using the rescue keyword, specifying cleanup actions using the always keyword, and applying conditions to entire blocks. Nested blocks can also be used for more complex workflows. Spacelift's ecosystem and GitOps flow can assist in managing and orchestrating Ansible playbooks.