Rocket sketches a dream laptop. "Huge screen! Giant battery! Fastest processor ever! And it fits in my pocket!" Raven looks at the drawing and tilts her head.
"What do you notice about the size? A huge screen and a pocket do not agree."
Nova draws a small seesaw in the air. "Would you like a hint? When one side goes up, the other side comes down. Designers call it a trade-off."
A trade-off means giving up a little of one thing to get more of another. Every design is full of them.
A bigger screen is easier to see. But it is heavier and uses more power. The battery runs out sooner.
A faster processor does more work each second. But it gets warmer and needs a fan. Fans take space and make noise.
More storage holds more files. But it takes room and uses power. A thin device has less room for it.
A bigger battery lasts longer. But it is heavier. A pocket device cannot hold a huge battery.
| If you want more | You give up some |
|---|---|
| Screen size | Light weight and battery time |
| Processor speed | Cool and quiet |
| Storage | Thinness |
| Battery time | Light weight |
| Small size | Big screen and big battery |
Trade-offs explain why computers come in different shapes. Each shape picks a different balance.
A desktop stays on a desk. It can be big, fast and cool, because it never moves. It plugs into the wall.
A laptop folds and travels. It trades some speed and screen size for a battery and a light body.
A tablet is thinner still. It trades a keyboard for a touchscreen and an even lighter body.
A tiny computer inside a thermostat has almost no screen. It trades nearly everything for small size and long life.
| Statement | True or false? |
|---|---|
| A bigger screen uses more power. | ? |
| A desktop can be bigger because it does not move. | ? |
| A faster processor stays cooler. | ? |
| A good designer gets everything with no trade-offs. | ? |
Rocket looks at the seesaw and crosses out pocket. "If I want a huge screen, it needs a bag," he says.
Then he crosses out fastest processor ever. "Homework does not need that. A medium one stays cooler."
His new sketch is a laptop. Medium screen, medium speed, a battery that lasts a school day. It fits the purpose.
Smart balancing! You can see the seesaw in every design now. Tomorrow you will design for people, not just for jobs. You will make a computer everyone can use.