The browser cache is the http cache store of the browser to cache a response (ie resource) previously fetched from a web server.
It's the last cache level of the HTTP cache chain. For general HTTP cache mechanism, see HTTP Caches - All the web caches layer explained on one page
Ater performing a conditional cache request, when the resource is served from the local browser cache, the request got a 304 - not modified status.
For one page: