What is multi-authentication in Laravel?

Multi-authentication allows different types of users (e.g., admins and regular users) to authenticate separately with their own guards and models. Configure in config/auth.php: add a new guard ("admin" => ["driver" => "session", "provider" => "admins"]) and a provider ("admins" => ["driver" => "eloquent", "model" => Admin::class]). Authenticate via specific guard: Auth::guard("admin")->attempt($credentials). Check authentication: Auth::guard("admin")->check(). Get current admin: Auth::guard("admin")->user(). Protect admin routes with the guard middleware: Route::middleware("auth:admin")->group(...). Each guard has separate session keys, so logging in as admin does not affect the user session and vice versa. Sanctum supports multiple guards as well for API token-based multi-auth.