Celsius and Kelvin are important in science for different reasons. Let’s break down what makes each of them special:

Celsius

• Everyday Use: Celsius is what most people use every day. It's the go-to scale for weather forecasts and studying the environment.
• Freezing and Boiling Points: In Celsius, water freezes at $0^\circ C$ and boils at $100^\circ C$ when there is standard air pressure.
• Understanding Temperature: Celsius helps us quickly understand temperatures that we feel every day, like in weather reports.

Kelvin

• Scientific Use: Kelvin is mainly used in science, especially in physics and chemistry. It’s really important in studying heat and gases.
• Starting Point: The Kelvin scale starts at absolute zero, which is $0 \text{ K}$. This is the point where everything stops moving. You can convert Celsius to Kelvin using the formula $K = C + 273.15$. So, $0^\circ C$ is the same as $273.15 \text{ K}$.
• Precise Measurements: Scientists use Kelvin when they need very accurate measurements, like when they are calculating changes in heat.

Conclusion

Celsius and Kelvin serve different purposes. Celsius is great for everyday use, while Kelvin is best for exact scientific work. In fact, more than 95% of scientific writing uses the Kelvin scale when talking about temperature.