Glossary A–Z.

A

AlgorithmA step-by-step set of instructions a computer follows to solve a problem or make a decision.Antimicrobial resistanceWhen bacteria, viruses, fungi or parasites evolve so that the medicines used against them stop working. Overuse of antibiotics speeds it up.Artificial intelligenceComputer systems that perform tasks normally needing human intelligence, such as understanding language, recognising images or making predictions. How we use AI tools is…

B

Black holeA region of space where gravity is so strong that nothing, not even light, can escape.

C

Clinical trialA study testing a medicine or treatment in people, usually in phases: small safety tests first, then larger trials of whether it works.

E

End-to-end encryptionScrambling a message so that only the sender and the recipient can read it — not even the service carrying it.EndemicA disease that is constantly present in a region at a fairly predictable level, unlike an epidemic, which is a sudden rise.ExoplanetA planet that orbits a star other than the Sun.

G

Gene editingChanging the DNA of a living thing at a precise place, most often with the CRISPR technique.Generative AIAI systems that produce new text, images, audio or video in response to a prompt, such as chatbots built on large language models.GenomeThe complete set of genetic instructions in an organism, written in its DNA.Geostationary orbitAn orbit about 35,786 km above the equator in which a satellite circles at the same speed as the Earth turns, so it stays over one spot. Used for communications and…

H

Herd immunityProtection of a whole community from an infection because enough people are immune that it cannot spread easily.

L

Large language modelAn artificial-intelligence system trained on very large amounts of text to predict and generate language. Chatbots are built on them; they can write fluently and still…Light-yearThe distance light travels in a year — about 9.46 trillion km. It measures distance, not time.Low Earth orbitOrbits up to about 2,000 km above the Earth’s surface, where the International Space Station and most satellites fly.

M

Machine learningA branch of artificial intelligence in which computers learn patterns from data instead of being given explicit rules.mRNA vaccineA vaccine that delivers messenger RNA instructing the body’s cells to make a harmless piece of a germ’s protein, which trains the immune system to recognise it.

N

NavICIndia’s own satellite navigation system, built by ISRO, covering India and the region around it.NeutrinoA subatomic particle with almost no mass and no electric charge that passes through ordinary matter almost without trace, which makes it extremely hard to detect.Nobel PrizeAnnual prizes for physics, chemistry, physiology or medicine, literature and peace, set up under the will of Alfred Nobel; a prize in economic sciences was added by…

O

OptogeneticsA technique that uses light to switch nerve cells on or off, after the cells have been genetically modified to make light-sensitive proteins.

P

PandemicAn epidemic that spreads across several countries or continents and affects large numbers of people. An epidemic is a sudden rise in cases in one area.Peer reviewChecking of a scientific paper by independent experts before a journal publishes it. It reduces errors but does not guarantee a finding is right.PhishingA scam in which a message pretends to come from a bank, a company or an official to trick you into giving away passwords, OTPs or money.PlaceboA dummy treatment with no active ingredient, used in trials to compare against the real one.

Q

Quantum computingComputing that uses quantum bits, which can be in a mix of states at once, to tackle some problems far faster than ordinary computers.

S

SemiconductorA material, usually silicon, whose ability to conduct electricity can be controlled. Chips made from semiconductors power almost every electronic device.Space debrisDead satellites, spent rocket stages and fragments left in orbit, which travel fast enough to damage working spacecraft.

T

Two-factor authenticationSigning in with two proofs of identity, such as a password and a code sent to your phone, so that a stolen password alone is not enough.