ASCII Table: Complete List Of Characters & Codes
The ASCII character table is a fundamental concept in computing, providing a standardized way to represent text using numerical codes. This article delves into the details of the ASCII table, explaining its history, structure, and practical applications. — Cowshed Backyard Ultra: Endurance Run
What is ASCII?
ASCII, which stands for American Standard Code for Information Interchange, is a character encoding standard for electronic communication. It defines a set of 128 characters, represented by the numbers 0 through 127. These characters include: — Creatine Side Effects: What You Need To Know
- Uppercase letters: A-Z
- Lowercase letters: a-z
- Digits: 0-9
- Punctuation marks: e.g., period, comma, question mark
- Control characters: e.g., newline, tab, carriage return
History of ASCII
Developed in the 1960s, ASCII aimed to create a universal standard for representing characters in computers. Before ASCII, different computers used different encoding systems, making it difficult to exchange data between them. ASCII helped solve this problem by providing a common standard that all computers could use.
Structure of the ASCII Table
The ASCII table is divided into several sections:
- Control Characters (0-31): These characters are used to control hardware devices or provide formatting. For example:
NULL (0)
: Represents an empty character.TAB (9)
: Represents a horizontal tab.LF (10)
: Represents a line feed (newline).CR (13)
: Represents a carriage return.
- Printable Characters (32-126): These characters can be displayed on a screen or printed on paper. They include letters, digits, and punctuation marks. For example:
Space (32)
: Represents a space character.A (65)
: Represents the uppercase letter 'A'.a (97)
: Represents the lowercase letter 'a'.0 (48)
: Represents the digit zero.
- Extended ASCII (128-255): This section is not part of the original ASCII standard and varies depending on the system. It often includes characters with diacritics, such as accented letters, and additional symbols.
Common ASCII Characters and Their Uses
Here are some commonly used ASCII characters and their corresponding decimal and hexadecimal values:
Character | Decimal | Hexadecimal | Description |
---|---|---|---|
NULL | 0 | 0x00 | Null character |
SOH | 1 | 0x01 | Start of Heading |
STX | 2 | 0x02 | Start of Text |
ETX | 3 | 0x03 | End of Text |
EOT | 4 | 0x04 | End of Transmission |
ENQ | 5 | 0x05 | Enquiry |
ACK | 6 | 0x06 | Acknowledge |
BEL | 7 | 0x07 | Bell (alert) |
BS | 8 | 0x08 | Backspace |
HT | 9 | 0x09 | Horizontal Tab |
LF | 10 | 0x0A | Line Feed (newline) |
VT | 11 | 0x0B | Vertical Tab |
FF | 12 | 0x0C | Form Feed |
CR | 13 | 0x0D | Carriage Return |
SO | 14 | 0x0E | Shift Out |
SI | 15 | 0x0F | Shift In |
DLE | 16 | 0x10 | Data Link Escape |
DC1 | 17 | 0x11 | Device Control 1 |
DC2 | 18 | 0x12 | Device Control 2 |
DC3 | 19 | 0x13 | Device Control 3 |
DC4 | 20 | 0x14 | Device Control 4 |
NAK | 21 | 0x15 | Negative Acknowledge |
SYN | 22 | 0x16 | Synchronous Idle |
ETB | 23 | 0x17 | End of Transmission Block |
CAN | 24 | 0x18 | Cancel |
EM | 25 | 0x19 | End of Medium |
SUB | 26 | 0x1A | Substitute |
ESC | 27 | 0x1B | Escape |
FS | 28 | 0x1C | File Separator |
GS | 29 | 0x1D | Group Separator |
RS | 30 | 0x1E | Record Separator |
US | 31 | 0x1F | Unit Separator |
Space | 32 | 0x20 | Space |
! | 33 | 0x21 | Exclamation mark |
" | 34 | 0x22 | Double quote |
# | 35 | 0x23 | Number sign |
$ | 36 | 0x24 | Dollar sign |
% | 37 | 0x25 | Percent sign |
& | 38 | 0x26 | Ampersand |
' | 39 | 0x27 | Single quote |
( | 40 | 0x28 | Open parenthesis |
) | 41 | 0x29 | Close parenthesis |
* | 42 | 0x2A | Asterisk |
+ | 43 | 0x2B | Plus sign |
, | 44 | 0x2C | Comma |
- | 45 | 0x2D | Hyphen |
. | 46 | 0x2E | Period |
/ | 47 | 0x2F | Slash |
0 | 48 | 0x30 | Digit 0 |
1 | 49 | 0x31 | Digit 1 |
2 | 50 | 0x32 | Digit 2 |
3 | 51 | 0x33 | Digit 3 |
4 | 52 | 0x34 | Digit 4 |
5 | 53 | 0x35 | Digit 5 |
6 | 54 | 0x36 | Digit 6 |
7 | 55 | 0x37 | Digit 7 |
8 | 56 | 0x38 | Digit 8 |
9 | 57 | 0x39 | Digit 9 |
: | 58 | 0x3A | Colon |
; | 59 | 0x3B | Semicolon |
< | 60 | 0x3C | Less-than sign |
= | 61 | 0x3D | Equals sign |
> | 62 | 0x3E | Greater-than sign |
? | 63 | 0x3F | Question mark |
@ | 64 | 0x40 | At symbol |
A | 65 | 0x41 | Uppercase A |
B | 66 | 0x42 | Uppercase B |
C | 67 | 0x43 | Uppercase C |
D | 68 | 0x44 | Uppercase D |
E | 69 | 0x45 | Uppercase E |
F | 70 | 0x46 | Uppercase F |
G | 71 | 0x47 | Uppercase G |
H | 72 | 0x48 | Uppercase H |
I | 73 | 0x49 | Uppercase I |
J | 74 | 0x4A | Uppercase J |
K | 75 | 0x4B | Uppercase K |
L | 76 | 0x4C | Uppercase L |
M | 77 | 0x4D | Uppercase M |
N | 78 | 0x4E | Uppercase N |
O | 79 | 0x4F | Uppercase O |
P | 80 | 0x50 | Uppercase P |
Q | 81 | 0x51 | Uppercase Q |
R | 82 | 0x52 | Uppercase R |
S | 83 | 0x53 | Uppercase S |
T | 84 | 0x54 | Uppercase T |
U | 85 | 0x55 | Uppercase U |
V | 86 | 0x56 | Uppercase V |
W | 87 | 0x57 | Uppercase W |
X | 88 | 0x58 | Uppercase X |
Y | 89 | 0x59 | Uppercase Y |
Z | 90 | 0x5A | Uppercase Z |
[ | 91 | 0x5B | Open square bracket |
\ | 92 | 0x5C | Backslash |
] | 93 | 0x5D | Close square bracket |
^ | 94 | 0x5E | Caret |
_ | 95 | 0x5F | Underscore |
` | 96 | 0x60 | Grave accent | | |||
a | 97 | 0x61 | Lowercase a |
b | 98 | 0x62 | Lowercase b |
c | 99 | 0x63 | Lowercase c |
d | 100 | 0x64 | Lowercase d |
e | 101 | 0x65 | Lowercase e |
f | 102 | 0x66 | Lowercase f |
g | 103 | 0x67 | Lowercase g |
h | 104 | 0x68 | Lowercase h |
i | 105 | 0x69 | Lowercase i |
j | 106 | 0x6A | Lowercase j |
k | 107 | 0x6B | Lowercase k |
l | 108 | 0x6C | Lowercase l |
m | 109 | 0x6D | Lowercase m |
n | 110 | 0x6E | Lowercase n |
o | 111 | 0x6F | Lowercase o |
p | 112 | 0x70 | Lowercase p |
q | 113 | 0x71 | Lowercase q |
r | 114 | 0x72 | Lowercase r |
s | 115 | 0x73 | Lowercase s |
t | 116 | 0x74 | Lowercase t |
u | 117 | 0x75 | Lowercase u |
v | 118 | 0x76 | Lowercase v |
w | 119 | 0x77 | Lowercase w |
x | 120 | 0x78 | Lowercase x |
y | 121 | 0x79 | Lowercase y |
z | 122 | 0x7A | Lowercase z |
{ | 123 | 0x7B | Open curly brace |
| | 124 | 0x7C | Vertical bar |
} | 125 | 0x7D | Close curly brace |
~ | 126 | 0x7E | Tilde |
DEL | 127 | 0x7F | Delete |
Practical Applications of ASCII
ASCII is used in various applications, including:
- Text editors: Representing characters in text files.
- Programming languages: Defining variables and keywords.
- Communication protocols: Transmitting data over networks.
- Printers: Controlling the formatting of printed documents.
ASCII vs. Unicode
While ASCII was a significant step forward, it only supports a limited set of characters, primarily those used in the English language. Unicode, on the other hand, is a more comprehensive character encoding standard that supports a much wider range of characters, including those from different languages and symbols.
Unicode uses a variable-length encoding scheme, such as UTF-8, which can represent characters using one to four bytes. This allows Unicode to support over a million different characters, making it suitable for representing text in virtually any language.
Why Unicode is Replacing ASCII
Unicode is gradually replacing ASCII because of its ability to support a broader range of characters. This is especially important in today's globalized world, where people from different countries and cultures need to communicate with each other using their native languages.
Conclusion
The ASCII character table is a foundational element in the world of computing. Understanding its structure and usage can provide valuable insights into how computers represent and manipulate text. While Unicode is becoming the dominant character encoding standard, ASCII remains relevant in many legacy systems and applications. By familiarizing yourself with the ASCII table, you can gain a deeper appreciation for the underlying principles of digital communication.
Further Reading:
Call to Action:
Explore the ASCII table and experiment with different characters to see how they are represented in various systems. Share your findings and insights with others to promote a better understanding of this essential concept. — Bob Stauffer: Oilers Broadcaster & Hockey Expert