A bit is one switch: 0 (off) or 1 (on).
Every time you add one bit, the number of patterns doubles.
How many bits?
Tap the switches. Your pattern lights up in the list below.
Why does it double?
Take every pattern you had before. Put a 0 in front of each one. Then put a 1 in front of each one. Same list, twice.
8 bits = 1 byte. After that, each unit is 1000 times bigger than the one before.
Going up to a bigger unit: divide. Going down to a smaller unit: multiply.
Type an amount
The units ladder
Internet speeds trap
Speeds use bits (small b: Mbps). File sizes use bytes (big B: MB). To turn Mbps into MB per second, divide by 8.
Each column has a value. Start at 1 on the right and double going left.
A 1 means "count this column". A 0 means "skip it". Add up the 1s.
Colour key
Each column always has the same colour, in every lesson.
Tap the switches
Challenge
Make this number with the switches above: 45
Go through the columns from biggest to smallest.
Ask one question each time: does this column fit into what is left? Yes = 1 and take it away. No = 0.
Cut the byte into two halves of 4 bits. Each half is worth 0 to 15.
Write each half as one symbol: 0 to 9, then A=10, B=11, C=12, D=13, E=14, F=15.
Tap the switches
Hex digits 0 to F
Blue box = first half. Orange box = second half.
Hex back to denary
The first digit is worth 16 each. The second digit is worth 1 each.
Add like normal, right to left, one column at a time.
The twist: 2 is written 10 in binary. So 1 + 1 = write 0, carry 1.
The only four rules
The sum
Tap the top two rows to change the numbers.
Slide every bit one place left = × 2.
Slide every bit one place right = ÷ 2. A bit that falls off the end is gone.
What happened
File size = how many things × bits for each thing.
Then turn bits into bytes (÷ 8), then into KB and MB (÷ 1000 each time).