A blockchain is a shared digital ledger that records transactions in linked groups called blocks. Copies of the ledger can be maintained across a network of computers. How a blockchain… Read more
Water continually moves through evaporation, condensation, precipitation, infiltration, and runoff. Energy from the Sun drives much of this circulation. Evaporation and transpiration Heat changes liquid water in oceans, lakes, rivers,… Read more
Sunlight contains many colors. When it enters Earth’s atmosphere, small gas molecules scatter shorter blue wavelengths more strongly than longer red wavelengths. What sunlight contains Visible sunlight is a mixture… Read more
Batteries store energy chemically and release it as electricity when needed. They power phones, laptops, vehicles, medical devices, tools, renewable-energy systems, and emergency backup equipment. How batteries work A battery… Read more
Renewable energy comes from sources that naturally replenish, including sunlight, wind, moving water, and geothermal heat. These resources can provide electricity and heat without relying exclusively on finite fossil fuels.… Read more
GPS receivers estimate location by comparing timing signals from multiple satellites. Because radio signals travel at a known speed, the time taken to arrive helps the receiver calculate the distance… Read more
Quantum computers use quantum bits, or qubits, whose states are managed according to quantum mechanics. Unlike ordinary bits, which represent either zero or one, qubits can be prepared in combinations… Read more
Robotics combines mechanical engineering, electronics, software, sensing, and control systems to build machines that act in the physical world. How robots operate Sensors collect information about the robot and its… Read more
Machine learning is a branch of artificial intelligence in which algorithms learn patterns from data and use those patterns to make predictions or decisions. Instead of writing every rule manually,… Read more
Artificial intelligence is the field of creating computer systems that perform tasks commonly associated with human intelligence, including recognizing patterns, understanding language, planning, generating content, and making predictions. How AI… Read more