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201 resultsWhat is moon phase? Plain-English meaning
A moon phase is the lit portion of the Moon visible from Earth as it orbits our planet. Learn the plain-English meaning, an example, and why it matters.
What is Moon phases? Plain-English meaning
Moon phases are the changing appearances of the Moon as seen from Earth, caused by the changing angle of sunlight illuminating the Moon's surface as it orbits...
What is multi factor authentication? Plain-English meaning
Multi factor authentication (MFA) is a security method that requires you to present two or more separate proofs of identity before you can access an account.
What is music? Plain-English meaning
Music is the intentional organization of sound and silence over time, often combining melody, harmony, rhythm, and expression to create an aesthetic experience.
What is nebula? Plain-English meaning
A nebula is a giant cloud of gas and dust in space, often the birthplace of stars or the remains of a dying star.
What is neural network? Plain-English meaning
A neural network is a computing system inspired by the brain that learns to recognize patterns from data.
What is neutron star? Plain-English meaning
A neutron star is the extremely dense, collapsed core left behind after a massive star explodes as a supernova.
What is nitrogen cycle? Plain-English meaning
The nitrogen cycle is the natural process by which nitrogen moves through the air, soil, water, and living organisms, changing forms as it goes.
What is ocean acidification? Plain-English meaning
Ocean acidification is the ongoing process by which the ocean becomes less alkaline (its pH decreases) as it absorbs carbon dioxide from the atmosphere...
What is ocean current? Plain-English meaning
An ocean current is a large-scale, continuous movement of seawater in a particular direction, driven by wind, temperature and salinity differences, and the...
What is ocean? Plain-English meaning
The ocean is the vast, continuous body of salt water that covers most of Earth's surface and plays a central role in the planet's weather, climate, and tides.
What is online reputation? Plain-English meaning
Online reputation is the overall impression of a person or organization that others form based on information available about them on the internet.
What is open source software? Plain-English meaning
Open source software is software whose source code is made available to anyone to view, modify, and distribute under a license that permits those activities.
What is operating system? Plain-English meaning
An operating system is the core software that manages a computer's hardware and software, providing a stable platform for applications to run.
What is orbit? Plain-English meaning
An orbit is the curved path that an object takes around another object in space due to gravity.
What is paleontology? Plain-English meaning
Paleontology is the scientific study of fossils to understand the history of life on Earth, including how organisms evolved, lived, and interacted with their...
What is particle physics? Plain-English meaning
Particle physics is the branch of science that studies the smallest known building blocks of matter and the forces through which they interact.
What is password hygiene? Plain-English meaning
Password hygiene is the practice of creating, storing, and using passwords in a way that makes your online accounts harder to break into.
What is photosynthesis? Plain-English meaning
Photosynthesis is the process by which green plants, algae, and some bacteria use sunlight, water, and carbon dioxide to make their own food (glucose) and...
What is planet formation? Plain-English meaning
Planet formation is the process by which dust and gas around a young star gradually clump together to build planets over millions of years.
What is planet? Plain-English meaning
A planet is a large round body that orbits a star, such as the Sun, and has cleared its orbit of other debris.
What is plate tectonics? Plain-English meaning
Plate tectonics is the scientific theory that Earth's outer shell is divided into several rigid plates that move over the softer mantle beneath, causing...
What is population growth? Plain-English meaning
Population growth is the change in the number of individuals in a population over time, calculated as births minus deaths plus net migration.
What is privacy settings? Plain-English meaning
Privacy settings are the controls in an app, website, or device that let you decide what personal information is collected, how it is used, and who can see it.
What is progressive web app? Plain-English meaning
A progressive web app is a website that uses modern web features, especially service workers, to work like a native installed app.
What is protein synthesis? Plain-English meaning
Protein synthesis is the biological process by which cells build proteins from amino acids using the instructions encoded in genes.
What is proxy server? Plain-English meaning
A proxy server is an intermediary computer that sits between your device and the internet, forwarding your requests and returning responses on your behalf.
What is QR code? Plain-English meaning
A QR code is a square, machine-readable pattern of black and white modules that stores information such as a website address, text, or contact details, which...
What is radio wave? Plain-English meaning
A radio wave is a type of electromagnetic radiation that travels through space at the speed of light and is used for wireless communication and radar.
What is rain forest? Plain-English meaning
A rain forest is a dense forest that receives a high amount of rainfall each year and is characterized by tall trees, a closed canopy, and high biodiversity.
What is rain? Plain-English meaning
Rain is liquid water that falls from clouds when water vapor in the air condenses into droplets heavy enough to fall to the ground.
What is renewable energy? Plain-English meaning
Renewable energy is energy obtained from sources that are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and...
What is rock cycle? Plain-English meaning
The rock cycle is the continuous process by which rocks on Earth's surface and interior change from one type to another over long periods of time.
What is satellite imagery? Plain-English meaning
Satellite imagery refers to pictures of Earth taken by satellites orbiting the planet, used to observe weather, oceans, land, and other features from space.
What is satellite? Plain-English meaning
A satellite is any object that orbits a larger body in space, including natural moons and human-made spacecraft.
What is scale of the universe? Plain-English meaning
The scale of the universe refers to the immense range of sizes and distances between cosmic objects, from small planets to vast galaxies and beyond.
What is season? Plain-English meaning
A season is a division of the year marked by changes in weather, ecology, and daylight hours, caused mainly by Earth's axial tilt as it orbits the Sun.
What is seasonal change? Plain-English meaning
Seasonal change is the regular shift in weather patterns and daylight hours that happens over the course of a year because Earth's axis is tilted as it orbits...
What is seismic wave? Plain-English meaning
A seismic wave is a pulse of energy that travels through the Earth, usually released when underground rocks suddenly break and slip.
What is service worker? Plain-English meaning
A service worker is a script that your browser runs in the background, separate from a web page, to enable features like offline access, background sync, and...
What is shooting star? Plain-English meaning
A shooting star is a bright streak of light in the sky caused by a small piece of space rock or dust burning up as it enters Earth's atmosphere.
What is smart device? Plain-English meaning
A smart device is an electronic device that connects to the internet or another network to send, receive, and process data, allowing it to be controlled or...
What is smart home? Plain-English meaning
A smart home is a residence equipped with internet-connected devices that can be monitored and controlled remotely, often automatically, to improve...
What is snow? Plain-English meaning
Snow is frozen precipitation that falls from clouds as ice crystals and accumulates on the ground when temperatures are cold enough.
What is software update? Plain-English meaning
A software update is a new version of a program that fixes security holes, adds features, or improves performance on your device.
What is soil erosion? Plain-English meaning
Soil erosion is the gradual removal of the top layer of soil by natural forces such as water and wind, or by human activities that disturb the land.
What is soil? Plain-English meaning
Soil is the loose, weathered material on the top layer of Earth's surface that supports plant life and is formed from the breakdown of rocks and organic matter.
What is solar eclipse? Plain-English meaning
A solar eclipse occurs when the Moon passes between the Sun and Earth, casting a shadow on Earth and temporarily blocking the Sun's light from part of our...
What is solar flare? Plain-English meaning
A solar flare is a sudden, intense burst of radiation from the Sun's surface, caused by the release of magnetic energy.
What is solar panel? Plain-English meaning
A solar panel is a device that converts sunlight into electricity using the photovoltaic effect.
What is solar system? Plain-English meaning
The solar system is the Sun and everything that orbits it, including planets, moons, asteroids, comets, and other small bodies.
What is space debris? Plain-English meaning
Space debris is any human-made object in orbit around Earth that no longer serves a useful purpose, such as old satellites, spent rocket stages, and fragments...
What is space probe? Plain-English meaning
A space probe is an uncrewed robotic spacecraft sent beyond Earth's orbit to collect data about space, planets, moons, or other celestial bodies.
What is space station? Plain-English meaning
A space station is a large spacecraft that orbits Earth and serves as a home and workplace for astronauts for long periods.
What is species diversity? Plain-English meaning
Species diversity is the variety and abundance of different species within a particular area or ecosystem.
What is speed of light? Plain-English meaning
The speed of light is the constant speed at which light travels through empty space, approximately 299,792 kilometers per second (about 186,282 miles per...
What is SSL certificate? Plain-English meaning
An SSL certificate is a digital file that verifies a website's identity and enables an encrypted HTTPS connection between a browser and the site.
What is star cluster? Plain-English meaning
A star cluster is a group of stars that are born together from the same cloud of gas and dust and remain bound together by gravity.
What is star formation? Plain-English meaning
Star formation is the process by which dense clouds of gas and dust in space collapse under their own gravity to create a star.
What is star? Plain-English meaning
A star is a massive, luminous sphere of plasma held together by its own gravity, which generates energy through nuclear fusion in its core.
What is storm surge? Plain-English meaning
Storm surge is the abnormal rise of water above the normal astronomical tide, caused primarily by strong winds pushing water toward the shore during a storm.
What is streaming service? Plain-English meaning
A streaming service is an online service that delivers audio or video content to your device over the internet in real time, so you can watch or listen without...
What is sunspot cycle? Plain-English meaning
The sunspot cycle is the roughly periodic change in the number of sunspots visible on the Sun's surface, driven by changes in the Sun's magnetic field.
What is supernova? Plain-English meaning
A supernova is a powerful and luminous explosion of a star that occurs at the end of its life cycle, briefly outshining an entire galaxy.
What is surface tension? Plain-English meaning
Surface tension is the tendency of a liquid's surface to shrink into the smallest possible area, behaving like a stretched elastic film.
What is swimming safety? Plain-English meaning
Swimming safety is the set of practices, rules, and precautions that reduce the risk of drowning and injury in or around water.
What is tectonic plates? Plain-English meaning
Tectonic plates are the large, rigid pieces of Earth's outer shell that move slowly over the softer rock beneath, causing earthquakes, volcanoes, and mountain...
What is telescope? Plain-English meaning
A telescope is an instrument that gathers light from distant objects and magnifies their image so that they appear closer and more detailed.
What is temperature gradient? Plain-English meaning
A temperature gradient is the rate at which temperature changes over a given distance, indicating how quickly heat conditions vary from one point to another.
What is tidal wave? Plain-English meaning
A tidal wave is a shallow-water wave caused by the gravitational pull of the Moon and the Sun, which creates the periodic rise and fall of the ocean surface...
What is tide pool? Plain-English meaning
A tide pool is a small body of seawater that remains in a depression or hollow on the shore after the ocean tide recedes.
What is tide? Plain-English meaning
A tide is the regular rise and fall of ocean water levels caused mainly by the gravitational pull of the Moon and the Sun on Earth.
What is tides? Plain-English meaning
Tides are the regular rise and fall of ocean water levels caused mainly by the gravitational pull of the Moon and, to a lesser extent, the Sun.
What is time zone? Plain-English meaning
A time zone is a region of the Earth that uses the same standard time, usually defined by its offset from Coordinated Universal Time (UTC).
What is time zones? Plain-English meaning
Time zones are geographical regions that share the same standard time, usually based on the position of the sun relative to the Earth's rotation.
What is topsoil? Plain-English meaning
Topsoil is the dark, nutrient-rich upper layer of soil that supports most plant roots and is essential for growing food and sustaining natural ecosystems.
What is tornado alley? Plain-English meaning
Tornado Alley is a loosely defined region in the central United States where tornadoes occur more frequently than in most other parts of the country.
What is transition zone? Plain-English meaning
A transition zone is a region where two different environments or systems meet and gradually blend, creating a distinct area with characteristics of both.
What is tree rings? Plain-English meaning
Tree rings are the concentric layers of wood that a tree adds each year, visible in a cross-section of the trunk, and they can be used to estimate the tree's...
What is ultraviolet light? Plain-English meaning
Ultraviolet light is a type of electromagnetic radiation with wavelengths shorter than visible light but longer than X-rays, invisible to the human eye.
What is urban heat island? Plain-English meaning
An urban heat island is a city or metropolitan area that is significantly warmer than its surrounding rural areas due to human activities and the built...
What is user interface? Plain-English meaning
A user interface is the part of a website, app, or device that you see and interact with, such as buttons, menus, and text fields.
What is vascular plants? Plain-English meaning
Vascular plants are plants that have specialized internal tissues (xylem and phloem) for transporting water, nutrients, and sugars throughout their bodies.
What is video call? Plain-English meaning
A video call is a live conversation between two or more people that includes both audio and moving video images transmitted over the internet.
What is volcano? Plain-English meaning
A volcano is an opening in Earth's surface where molten rock, ash, and gases escape from below.
What is walking exercise? Plain-English meaning
Walking exercise is a form of physical activity that involves moving at a steady pace to improve or maintain health, and it can be easily incorporated into...
What is water table? Plain-English meaning
The water table is the upper surface of the zone in the ground where all pore spaces and cracks are completely filled with water.
What is weather forecast? Plain-English meaning
A weather forecast is a scientifically based estimate of future atmospheric conditions, such as temperature, precipitation, wind, and cloud cover, for a...
What is weather front? Plain-English meaning
A weather front is the boundary between two air masses with different temperatures, humidity, or density, which often brings changes in wind, clouds, and...
What is weather station? Plain-English meaning
A weather station is a facility with instruments that measure atmospheric conditions such as temperature, humidity, air pressure, wind speed, and precipitation...
What is web browser? Plain-English meaning
A web browser is a software application that retrieves and displays web pages from the internet on your device.
What is web cookie? Plain-English meaning
A web cookie is a small text file that a website stores in your browser to remember information about you across visits or requests.
What is web server? Plain-English meaning
A web server is a computer system that stores website files and delivers them to your browser over the internet when you request a page.
What is web standards? Plain-English meaning
Web standards are agreed-upon technical specifications that define how web technologies should work to ensure consistency, interoperability, and accessibility...
What is web storage? Plain-English meaning
Web storage is a browser feature that lets websites save data on your device using localStorage (persists) or sessionStorage (cleared when the tab closes).
What is wind power? Plain-English meaning
Wind power is the process of converting the kinetic energy of moving air into electricity, typically using large turbines that spin a generator.
What is wind turbine? Plain-English meaning
A wind turbine is a machine that converts the kinetic energy of moving air into mechanical power, usually to generate electricity.
What is wind? Plain-English meaning
Wind is the natural movement of air from an area of higher pressure to an area of lower pressure, caused by differences in temperature and the Earth's rotation.
What is winter solstice? Plain-English meaning
The winter solstice is the moment when one of Earth's poles reaches its maximum tilt away from the Sun, producing the shortest day and longest night of the...
What is x-ray astronomy? Plain-English meaning
X-ray astronomy is the branch of astronomy that studies celestial objects by detecting the X-rays they emit.