How to get a value, from bucket, using the REST API

Can someone provide an example, of how someone using a REST tool, for example Rest console, of postman, could retrieve a value stored in a bucket, by providing key,bucket credentials,or/and server credentials?
thanks in advance

The REST API in Couchbase Server is generally used to manage clusters, server nodes, and buckets, and to retrieve run-time statistics within your Couchbase Server deployment.

Data operations, such as set and get for example, are best handled by Couchbase SDKs. (Check out http://www.couchbase.com/communities/all-client-libraries to download Couchbase SDK in the language of your choice).

Thanks,
D