Bits and Bytes

< CS101

At the smallest scale in the computer, information is stored as bits and bytes. In this section, we'll look at how that works.

Bit

Everything in a computer is 0's and 1's ... what does that mean? The bit stores just a 0 or 1 .. it's the smallest building block of storage.

Byte

How much exactly can one byte hold?

Number of bits Distinct Patterns
1 0 1
2 00 01 10 11
3 000 001 010 011
100 101 110 111
Number of bits Distinct Patterns
1 0 1
2 00 01 10 11
3 000 001 010 011
100 101 110 111

One Byte - 256 Patterns

Bytes

The space that data takes up in the computer is measured in by the "byte". One byte is big enough to hold a single typed letter, like 'a'. Here we'll look at storing data in RAM memory and in persistent storage like a hard drive. All of that storage space will be measured in bytes. We'll look at byte arithmetic in more detail later.

Bytes and Letters - ASCII Code

32 space
33 !
34 "
35 #
36 $
37 %
38 &
39 '
40 (
41 )
42 *
43 +
44 ,
45 -
46 .
47 /
48 0
49 1
50 2
51 3
52 4
53 5
54 6
55 7
56 8
57 9
58 :
59 ;
60 <
61 =
62 >
63 ?
64 @
65 A
66 B
67 C
68 D
69 E
70 F
71 G
72 H
73 I
74 J
75 K
76 L
77 M
78 N
79 O
80 P
81 Q
82 R
83 S
84 T
85 U
86 V
87 W
88 X
89 Y
90 Z
91 [
92 \
93 ]
94 ^
95 _
96 `
97 a
98 b
99 c
100 d
101 e
102 f
103 g
104 h
105 i
106 j
107 k
108 l
109 m
110 n
111 o
112 p
113 q
114 r
115 s
116 t
117 u
118 v
119 w
120 x
121 y
122 z
123 {
124 |
125 }
126 ~

Typing, Bytes, and You


typed letters correspond to bytes in RAM