Whether you are using Couchbase for simple caching or as the NoSQL database for an application, your most common operations are going to be getting and setting data.
Data is most commonly a JSON document, but can really be any string you want including binary representations of serialized objects.
For the comprehensive list of SDK methods, parameters, descriptions, and code samples, please look in the API Docs (in the download). Click on the cfcouchbase package and then the CouchbaseClient class.