The document presents a case study analysis of HDFC Bank's net banking and telebanking systems according to various usability principles. It analyzes the basic UI framework of the net banking system and the voice-guided response system of the telebanking system. The analysis follows Norman's model of human action and applies principles like visibility, feedback, affordance, mapping, constraints, and consistency. It also demonstrates how HDFC Bank provides informative feedback, allows easy reversal of actions, and reduces short-term memory load on its net banking platform.