Cache directive "no-cache"

An explaination of the HTTP Cache-Control header

The Cache-Control header is used to specify directives for caching mechanisms in both HTTP requests and responses.

A typical header looks like this Cache-Control: public, max-age=10

Indicates that the response may be cached by any cache.
Indicates that the response is intended for a single user and must not be stored by a shared cache. A private cache may store the response.
Forces caches to submit the request to the origin server for validation before releasing a cached copy.