What is a robot: from a vacuum cleaner to a humanoid

A robot is a machine that uses sensors to perceive the world around it, processes that information and carries out physical actions on its own: it moves, carries things, cleans, welds or delivers.

A robot senses the world, decides and acts by itself

In plain words

A microwave can heat food, but it has no idea what is inside it. A robot vacuum is different: it "sees" walls, "feels" drops, plans its own route and returns to its dock when the battery runs low. That is the difference: a robot senses, thinks and acts by itself - even if only within simple limits.

How it works

Sensors (cameras, lidars, bump switches, gyroscopes) collect information about the world.
The controller - the robot's "brain" - processes this data using a program or AI.
The program decides what to do next: drive, turn, grab, stop.
Actuators - motors and drives - carry out the movement.
The robot checks the result with its sensors and adjusts - this loop repeats dozens of times a second.

The loop every robot runs: sense, decide, act

Where you'll see it

At home: robot vacuums, window cleaners, lawn mowers, toy and educational robots. In factories: robotic arms that weld and paint. In warehouses: robotic carts. On the streets: drones, delivery robots, cars with autopilot. In medicine: surgical robots controlled by a doctor.

Does it matter when buying

For the home, robot vacuums are the most popular, and what matters there is the navigation type, suction power and self-emptying station. For learning, there are kits like LEGO, Arduino or micro:bit to build your own robot. I think this is one of the best ways to understand how technology works from the inside.

Myths

Myth: A robot is always a metal human. Reality: Most robots look nothing like people: they are vacuums, robotic arms, carts and drones.
Myth: Robots never make mistakes. Reality: They make mistakes when something happens that the program did not foresee: an unusual object, poor lighting, a slippery floor.

FAQ

Is a robot the same as AI?

No. AI is a program; a robot is a machine with a body. A robot can use AI or run on a simple program.

Where does the word "robot" come from?

It was coined in Karel Čapek's 1920 play; it comes from the Czech word "robota", meaning hard labour.

Can I build a robot myself?

Yes, educational kits let you start even with no experience.