What Is a Laptop? How a Whole Computer Learned to Fold Up
A laptop is not a smaller kind of computer. It is a whole computer, with its screen, keyboard and power folded into one box you can carry.
The whole idea, in one diagram
A desktop is four separate things: a tower, a screen, a keyboard and a wall socket.
A laptop is all four in one hinged box, with a battery instead of the socket.
Nothing about the job changed. Only the shape, the weight and the freedom changed.
What problem did it solve?
A computer lived in one room, on one desk, plugged into one wall. If your work was on that machine, then you had to be in that room. A journalist, a doctor on a ward or a child doing homework at a grandparent's house simply could not reach it.
Engineers squeezed the screen, the keyboard, the processor, the storage and a rechargeable battery into a single hinged case that shuts like a book.
Work and school stopped needing a fixed place. Lessons happen on trains, reports get written in cafes, and an engineer can carry the same machine to a factory, a home and a classroom in one day.
How it started
- 1968 to 1972
The Dynabook is imagined
ðĪ Alan Kay, USA
Long before it was possible, Alan Kay described a notebook-sized computer that children could carry everywhere and use to draw, write and make music. He called it the Dynabook and it was never built.
Why it mattered: It set the target. Almost every laptop and tablet since has been an attempt to build the machine he described, and he designed it for children first.
- 1975
The first computer you could carry, just about
ðĪ IBM, USA
The IBM 5100 was advertised as portable. It weighed about 25 kilograms, roughly the same as a large suitcase full of books, and still needed a wall socket.
Why it mattered: It proved the idea was wanted. It also proved that portable means nothing until you solve weight and power.
- 1981
The Osborne 1 goes on sale
ðĪ Adam Osborne, USA
The first portable computer people actually bought in numbers. It folded shut like a sewing machine, weighed about 11 kilograms and had a screen just 13 centimetres across.
Why it mattered: It showed there was a real market for carrying your computer with you, even when carrying it hurt your arm.
- 1982
The first fold-up laptop
ðĪ GRiD Systems, USA. Designed by Bill Moggridge.
The GRiD Compass was the first computer with the shape we now call a laptop: a screen that folds down flat onto the keyboard. NASA took it aboard the Space Shuttle.
Why it mattered: That hinge is the whole invention. Every laptop on Earth still uses the shape it introduced, and it went to space before it went to most offices.
- 1985
Laptops become normal
ðĪ Toshiba and others
The Toshiba T1100 was light enough, cheap enough and battery-powered enough for ordinary businesses to buy in quantity.
Why it mattered: This is when a laptop stopped being special equipment and started being just what a computer looked like when you travelled.
- 1991
The lithium-ion battery arrives
ðĪ Sony, building on work by Whittingham, Goodenough and Yoshino
A rechargeable battery that held far more energy for its weight went on sale. Its inventors later shared the 2019 Nobel Prize in Chemistry.
Why it mattered: Without it a laptop runs for twenty minutes and is useless. Every portable device you own, including your phone, depends on this one chemistry.
- 1991
The keyboard moves back, and a palm rest appears
ðĪ Apple, with the PowerBook
Instead of putting the keyboard at the front edge, designers pushed it back and left space for your wrists, with a pointing device in the middle.
Why it mattered: It sounds tiny. It is the reason a modern laptop is comfortable to type on for hours, and every maker copied it.
- 2008 onwards
Thin, silent and all day
ðĪ Many makers
Spinning hard disks were replaced by silent chips, processors learned to sip power, and screens got brighter while using less of it.
Why it mattered: A laptop that lasts a whole school day without a charger changed how they are used. You stop planning your day around finding a socket.
Who made it happen
Alan Kay
born 1940 · USA
Described the Dynabook in 1972, a carry-anywhere computer designed for children. Laptops and tablets are still chasing his idea.
Bill Moggridge
1943 to 2012 · England and USA
Designed the GRiD Compass in 1982, the first computer with a screen that folds onto the keyboard.
Adam Osborne
1939 to 2003 · Thailand, England and USA
Built and sold the Osborne 1 in 1981, the first portable computer that a lot of people actually bought.
John Goodenough
1922 to 2023 · USA
Shared the 2019 Nobel Prize for the lithium-ion battery, the thing that makes a portable computer possible at all.
Akira Yoshino
born 1948 · Japan
Built the first safe, practical lithium-ion battery for real products, shared the same Nobel Prize.
Stanley Whittingham
born 1941 · England and USA
Discovered the first working lithium battery design in the 1970s, the starting point for all the rest.
How a laptop fits a whole computer into a bag
- 1
It carries its own power
A battery stores electricity as chemistry and releases it slowly. When you plug in a charger you are pushing the chemistry backwards so it can be used again. This is why a battery wears out after a few years.
- 2
It keeps itself cool in a tiny space
Chips make heat, and heat inside a thin box is dangerous. A laptop uses metal pipes and a small fan to move heat to the edges, and it will deliberately slow itself down rather than overheat.
- 3
Everything is chosen to be light and low power
The screen, the storage and the processor are all versions designed to use less electricity than a desktop's. That is why a desktop is usually faster for the same money.
- 4
The hinge does the folding
The screen folds flat onto the keyboard, which protects both of them and halves the size. Wires run through the hinge, and that is why a broken hinge is such an expensive repair.
- 5
It connects without wires
Wi-Fi and Bluetooth radios are built in, so the last cable disappears too. A laptop with a good battery and Wi-Fi needs no wires at all for hours.
Each invention solved the last one's problem
Desktop computer
- Problem before
- Four separate lumps that live on one desk and must be plugged into a wall.
- What it solved
- Brought a real computer into homes, schools and small offices for the first time.
- Impact
- Powerful and cheap for what you get, and completely stuck in one room.
Portable, or luggable
- Problem before
- You could not take your work anywhere at all.
- What it solved
- Everything was packed into one case with a handle, so you could move it between places.
- Impact
- About 11 kilograms, a tiny screen, and still needing a socket. Better than nothing, and genuinely heavy.
Laptop
- Problem before
- A luggable was too heavy to use on the move and had no useful battery.
- What it solved
- The fold-up hinge plus a real rechargeable battery made it usable on your lap, on a train, anywhere.
- Impact
- Work and school stopped depending on a place. This is still the shape most work happens on.
Smartphone
- Problem before
- Even a laptop has to be taken out, opened and set down somewhere.
- What it solved
- The whole computer shrank into a slab of glass you never put away, always connected.
- Impact
- The next page in this series. Most people on Earth now use one as their only computer.
A laptop is not a weaker computer. It is the same computer with the power supply, the screen and the keyboard folded in, and every design choice traded for weight and battery life.
Find a laptop at home and gently lift the lid, then look at the hinge. Every wire for the screen, the camera and the microphone runs through that little joint, and it has to survive being opened and closed thousands of times. Then check how warm the air is at the back after a video has been playing for a while.
Quiz: how much did you remember?
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Questions about laptops
What is a laptop in simple words?
A laptop is a complete computer with its screen, keyboard and battery built into one case that folds shut like a book, so you can carry it and use it without plugging it into a wall.
Who invented the laptop?
There is no single inventor. Alan Kay imagined one in 1972, the Osborne 1 was the first portable people really bought in 1981, and the GRiD Compass in 1982 was the first with the fold-up shape we still use.
What is the difference between a laptop and a desktop?
A desktop is separate pieces that stay in one place and plug into the wall. A laptop is all those pieces in one box with a battery. For the same price a desktop is usually faster, because it has more room for cooling and does not have to save power.
Why does a laptop battery get worse over time?
A battery works by pushing chemistry one way and then back again. Every full charge wears the chemistry very slightly. After a few hundred cycles it holds noticeably less, which is normal rather than a fault.
Why does my laptop get hot and noisy?
Chips turn electricity into work and into heat. In a thin case the heat has nowhere to go, so a small fan pushes it out. If the machine cannot stay cool it slows itself down on purpose to protect itself.
Is a tablet a laptop?
Not quite. A tablet is a screen you touch, usually with no keyboard attached and often running phone-style software. Add a keyboard and it starts to behave like a laptop, which is why the two keep getting closer together.
Why are laptops usually more expensive than desktops?
Making parts small, light and low power is harder than making them big. You are paying for the engineering that fits a whole computer, a screen and a battery into a box you can carry.
What does the hinge have to do with anything?
More than you would think. Every wire for the screen and the camera passes through it, and it must survive thousands of open and close cycles. It is one of the most common things to break and one of the most costly to fix.
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