Session

• session for each user, which you can store small amounts of data, persisting between requests
• session is only available in the controller and view, with access to a number of storage mechanisms
  • ActionDispatch::Session::CookieStore, stores everything on the client
  • ActionDispatch::Session::CacheStore, data in the Rails cache
  • ActionDispatch::Session::ActiveRecordStore, stores the data in a database
• all sessions use a cookie to store a unique ID for each session
• session[:myKey] = val adds a value to the sessions hash

Cookies

• Applications store small amounts of data on the client, persisting across requests and even sessions
• cookies[:myKey] = val
• cookies.encrypted[:expiration_date] = Date.tomorrow

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