What is the session system in Laravel?

Laravel provides a unified API for various session backends. Configure the driver in .env: SESSION_DRIVER=database (or file, redis, memcached, cookie, array). Store data: session()->put("key", "value") or $request->session()->put(...). Retrieve: session("key", "default"). Flash data (available only for next request — great for success messages): session()->flash("status", "Profile updated!"). Retrieve and delete: session()->pull("key"). Delete: session()->forget("key"). Clear all: session()->flush(). The all() method returns all session data. Increment/decrement: session()->increment("views"). Use Redis for sessions in production for performance and to support multiple servers.