bytes

Last updated May 31, 2022.

# Unit of digital information

0 or 1, 1bit

00 01 10 11 2 bits

…

11111111 8 bits (1 byte)

KiloBytes

MegaBytes

GigaBytes

TeraBytes

PettaBytes

ExaBytes

ZettaBytes

YottaBytes

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
0 0
01 1
10 2
11 3
100 4
1000 8
10000 16
100000 32
1000000 64
10000000 128
11111111 255

power of two

overflow = infinite of x resource in games = negative number

1
2
11111111 255 FF
-1

7F half, nibble

unsigned example 0 to 255

signed example -127 to 128

word, double word, quad word

2 bytes, 4 bytes, 8 bytes

when dealing with multiple bytes: know the endianness big endian and little endian

big endian: first bytes are the most significant little endian: last bytes are the most significant

7f is 127 which is 011111111

80 is 128 and notice how that is 100000000

f is last digit in hex so the 7 becomes 8 and f goes back to 0

Since FF is 1 byte which is 8 bits

A bit is 0 or 1 so 8 bits goes from 00000001 to 11111111

Unsigned and signed mean how the first digit is used

If the first digit is 1 then negative number

If the first digit is 0 then positive number

the first 4 bytes of any file is the file signature

the file size of the file is specified somewhere in the first bytes too, but i forgot where