The Kardashev scale is a theoretical scale that measures a civilization's level of technological advancement based on its use and ability to harness and use energy. The scale was originally proposed by the Soviet Russian astrophysicist Nikolai Kardashev in 1964 and has been expanded on by other people. It has since become an important way of classifying civilizations based on their technological capabilities.
Currently we do not know any other civilization so we may be making incorrect assumptions based on ourselves. We know that humans are curious, competitive, greedy for resources and expansionist. These characteristics made us able to take over our planet, so it is reasonable to assume that extraterrestrials able to take over their home planet also have these qualities. If extraterrestrials also follow the same laws of physics, then there is a way to measure progress: energy use.
The scale consists of five types of civilizations: Type I, Type II, Type III, Type IV and Type Ω.
A Type I civilization can harness all the energy available on its planet. This includes harnessing energy from renewable sources such as wind, solar, and hydroelectric power, and non-renewable sources like fossil fuels. A Type I civilization is also able to prevent natural disasters such as earthquakes and hurricanes. A Type II civilization is also able to colonize other planets and control their climate. A Type II civilization can also harness all the available energy produced by its star and planetary system. This includes building structures around the star to capture its energy such as a Dyson sphere/ swarm and using it to power its civilization. A Type III civilization can harness all the energy produced by its entire galaxy. This includes building massive structures like Dyson spheres or swarm worlds to capture and use the energy produced by all the stars in its galaxy. A Type IV civilization can manipulate matter and energy on a galactic scale. They would have complete control over the resources and energy of their entire galaxy. A Type Ω civilization is the most advanced civilization. It can harness the energy of the entire universe and is billions or trillions of times more advanced than a Type IV civilization. It may be able to create new universes or manipulate the very fabric of reality itself.
As of now, humanity is considered a Type 0.73 civilization on the Kardashev scale. We are still heavily reliant on fossil fuels and have yet to harness the full potential of renewable energy sources. However, some experts predict that humanity will reach Type I in the next few centuries.
In conclusion, the Kardashev scale is a valuable tool for discussing and classifying civilizations based on their technological capabilities. Not only does it provide a measurement to classify civilizations based on their energy usage and help us understand the potential capabilities of advanced civilizations, but it also allows us to imagine what technologies and capabilities may exist in the future.