Hexes and the Magic of 16 🔮
@vaidehijoshi
there are a lot of
ways to do something
different
you can write numbers in lots of different ways
(it really just depends on how many digits you want to use)
10 digits:
base 10
2 digits:
base 2
/ denary
/ binary
16 digits:
base 16
/ hexadecimal
➡️ 205
➡️ 11001101
➡️ . . . ?
base
are possible per place value
digits
refers to how many
| base 2 | base 10 | base 16 |
|
|
|
A, B, C,
D, E, F
0, 1
0, 1, 2, 3, 4,
5, 6, 7, 8, 9
0, 1, 2, 3, 4,
5, 6, 7, 8, 9
10 digits:
base 10
2 digits:
base 2
/ denary
/ binary
16 digits:
base 16
/ hexadecimal
➡️ 205
➡️ 11001101
➡️ CD
yes, really
➡️ 3 digits in base 10
205
➡️ 8 digits in base 2
➡️ 2 digits in base 16
11001101
205
CD
🆗
but...why does that matter?
🆒
11001101
1
1 bit
1 byte
11001101
8 digits === 1 byte
the fewer the digits,
the more information,
in a tiny amount of space.
💡
2 digits === 1 byte
8 digits === 1 byte
#EC152E
rgb(236, 21, 46)
===
#EC152E
rgb(236, 21, 46)
2E
15
EC
46
21
236
236
3 bytes
21
46
r
g
b
rgb(236, 21, 46)
236
21
46
r
g
b
RGB color model
additive color
theory of trichromatic color vision
#FFFFFF
#000000
#EC152E
2E
15
EC
1 byte
1 byte
1 byte
256 permutations
256
256
256
x
x
=
16,777, 216
any number from 0-255
16 x 16
=
256
hexes are everywhere!
👀
I got 128 problems, but encoding ain’t one
🙈
"Ruby"52 75 62 79
01010010 01110101 01100010 01111001
0
0
0
0
é
ø
æ
2 = 128
7
2 = 8
256
magic numbers (hexspeak)
🙊
0xB000 0xDEAD
0xDEADFA11
0xD15EA5E
internet protocol v6
🙉
8 groups of 4 hexes
2 bytes, 16 bits
2b2b:1821:a9ih:0000:0000:ff91:9ab0:1ee3
surprise!
🐒
hexes are in rails, too
type :binary
SecureRandom.hex
app_secret
#EC152E
111011000001010100101110
abstractions are powerful, necessary tools.
but sometimes they're used as a weapons.
This is worthy of a conference talk? This is week 1 freshman computer science stuff. "
never allow other people to use abstractions to intimidate you.
use them as a tool to empower you.
🔑
abstractions
they're not magic!
abstractions are just that :
💫
understanding abstractions is what them magical
makes
medium.com/basecs✨
@vaidehijoshi
