What are the different models available in the Shimano derailleur lineup?

The Shimano derailleur lineup includes various models such as the Shimano Tourney, Shimano Altus, Shimano Acera, Shimano Alivio, Shimano Deore, Shimano SLX, Shimano Deore XT, and Shimano XTR. Each model offers different features and performance levels to suit different riding needs and preferences.