Kant's Categorical Imperative is a special idea in moral philosophy. It stands out from other ethical theories because of its unique principles and how they are used.

Universal Rules and Reason
The main idea of the Categorical Imperative is that our actions should be something everyone can agree on. Unlike other theories that judge actions based on their results, Kant believes the rightness of an action comes from whether it can be made into a rule everyone would follow. This means we should act in a way that could be accepted by everyone, putting our duty first instead of just focusing on the results.

Strict Moral Rules
Many ethical systems allow some flexibility based on the situation, like utilitarianism, but Kant's philosophy is strict. He believes that moral rules must be followed without exceptions. This means that the intentions behind our actions are very important, which sets Kant's ideas apart from those that change based on different situations.

Respect and Worth
The Categorical Imperative also highlights the value of all people. Kant argues that we should treat ourselves and others as valuable on their own, not just as tools for achieving something else. This promotes respect and dignity, which many outcome-based theories lack, as they might prioritize the greater good over individual rights.

Simple and Useful
The Categorical Imperative is easy to understand and provides clear guidance for making ethical decisions. It skips the complicated calculations of results that come with utilitarianism or the different views present in virtue ethics. This straightforwardness makes it a strong tool in moral philosophy.

In short, the Categorical Imperative is unique because of its focus on universal rules, strict moral codes, respect for individuals, and clear guidance. This creates a strong foundation for Kant's moral philosophy.