There are two types of resources that are being used. The first one is letter A and the other resource is letter B. The lightning component framework is a type of UI framework that is usually created for creating single page applications not only for mobile services but also for desktop services.
This type of framework makes use of two types of programming models namely Lightning Web Components Model and Aura Components Model.
This can be effective in providing responsive components that may be required by different components. Developers would need to be familiar with this type of framework and its differences with the others that are available.