🧠 What Does It Mean to “Remember”?
When you remember something, it’s in your brain.
When a computer remembers something… it’s just a switch that stays in the same position.
Memory for a machine means:
“I flipped a switch to ON… and I didn’t flip it back.”
That’s it.
🔁 The Tiny Box That Remembers
Let’s build a memory box.
It has:
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One button that turns ON
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Another button that turns OFF
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A light that shows what state it’s in
Once you press ON, the light stays on—even if you don’t press anything else.
That’s memory!
This simple idea is called a latch.
It “latches onto” a state (ON or OFF) and holds it.
🔄 Set and Reset
The memory box has two buttons:
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SET = turn it ON
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RESET = turn it OFF
It only changes when you press one of those.
If you leave it alone, it holds the last thing you told it.
That’s how your phone:
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Saves your message
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Stores your score
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Remembers your name
🧱 Building Bigger Memory
One latch = 1 bit of memory. That’s enough to remember:
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YES or NO
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ON or OFF
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1 or 0
Want to remember a whole word?
You’ll need 8 latches. That’s 1 byte.
Want to store a picture? You’ll need millions.
That’s why computers have:
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RAM (short-term memory)
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Hard drives (long-term memory)
Both use switches. Just more of them.
Volatile vs Permanent
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RAM = forgets everything when power is off
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Hard drive = keeps everything even when power is gone
But both work on the same rule:
“Keep a signal locked in place.”