ASCII Table

ASCII (American Standard Code for Information Interchange) is a standard character encoding used in telecommunication. The ASCII pronounced ‘ask-ee’ , is strictly a seven bit code based on English alphabet. ASCII codes are used to represent alphanumeric data . The code was first published as a standard in 1967. it was subsequently updated and published as  ANSI X3.4-1968, then as ANSI X3.4-1977 and finally as ANSI X3.4-1986. Since it is a seven bit code , it can at the most represent 128 characters. it currently defines 95 printable characters including 26 upper case letters (A to Z) , 26 lower case letters , 10 numerals (0 to 9) and 33 special characters including mathematical symbols, punctuation marks and space character. They represent text in, telecommunications equipment, and devices. These include numbers, upper and lowercase English letters, functions, punctuation symbols, and some other symbols. In total, there are 256 ASCII characters, and can be broadly divided into three categories: 

1. ASCII control characters (0-31 and 127)
2. ASCII printable characters (32-126) (most commonly referred)
3. Extended ASCII characters (128-255)

Below are the ASCII values of printable characters (33, 126):

Character	Character Name	ASCII code		Character	Character Name	ASCII code		Character	Character Name	ASCII code
!	Exclamation point	33		A	Uppercase a	65		a	Lowercase a	97
“	Double quotation	34		B	Uppercase b	66		b	Lowercase b	98
#	Number sign	35		C	Uppercase c	67		c	Lowercase c	99
$	Dollar sign	36		D	Uppercase d	68		d	Lowercase d	100
%	Percent sign	37		E	Uppercase e	69		e	Lowercase e	101
&	ampersand	38		F	Uppercase f	70		f	Lowercase f	102
‘	apostrophe	39		G	Uppercase g	71		g	Lowercase g	103
(	Left parenthesis	40		H	Uppercase h	72		h	Lowercase h	104
)	Right parenthesis	41		I	Uppercase i	73		i	Lowercase i	105
*	asterisk	42		J	Uppercase j	74		j	Lowercase j	106
+	Plus sign	43		K	Uppercase k	75		k	Lowercase k	107
,	comma	44		L	Uppercase l	76		l	Lowercase l	108
–	hyphen	45		M	Uppercase m	77		m	Lowercase m	109
.	period	46		N	Uppercase n	78		n	Lowercase n	110
/	slash	47		O	Uppercase o	79		o	Lowercase o	111
0	zero	48		P	Uppercase p	80		p	Lowercase p	112
1	one	49		Q	Uppercase q	81		q	Lowercase q	113
2	two	50		R	Uppercase r	82		r	Lowercase r	114
3	three	51		S	uppercases	83		s	Lowercase s	115
4	four	52		T	Uppercase t	84		t	Lowercase t	116
5	five	53		U	Uppercase u	85		u	Lowercase u	117
6	six	54		V	Uppercase v	86		v	Lowercase v	118
7	seven	55		W	Uppercase w	87		w	Lowercase w	119
8	eight	56		X	Uppercase x	88		x	Lowercase x	120
9	nine	57		Y	Uppercase y	89		y	Lowercase y	121
:	colon	58		Z	Uppercase z	90		z	Lowercase z	122
;	semi-colon	59		[	Left square bracket	91		{	Left curly brace	123
<	Less-than sign	60		\	backslash	92		|	Vertical bar	124
=	Equals sign	61		]	Right square bracket	93		}	Right curly brace	125
>	Greater-than sign	62		^	caret	94		~	tilde	126
?	Question mark	63		_	underscore	95
@	At sign	64		`	Grave accent	96

So what’s before 33 and beyond 126?

1. ASCII values before 32 (0-31) are control characters. A character code is often used in in-band signaling as a reference point in a set of characters to avoid adding additional symbols to the text.
2. At 32, we have space, it is included as printed characters, however, it’s not wrong to say space could also serve as a control character.
3. At 127, we have DEL (delete), which is a control character.
4. After 127, (128-255), we have Extended ASCII characters representing mathematical and other symbols that are not represented as keys and are not used in general.

Below are the ASCII values of control characters (0-31, 127):

Character	Character Name	ASCII Code		Character	Character Name	ASCII Code		Character	Character Name	ASCII Code
NULL	Null character	00		VT	Vertical tab	11		SYN	Synchronous idle	22
SOH	Start of header	01		FF	Form feed	12		ETB	End of trans. Block	23
STX	Start of text	02		CR	Carriage return	13		CAN	cancel	24
ETX	End of text	03		SO	Shift out	14		EM	End of medium	25
EOT	End of transmission	04		SI	Shift in	15		SUB	substitute	26
ENQ	enquiry	05		DLE	Data link escape	16		ESC	escape	27
ACK	acknowledge	06		DC1	Device control 1	17		FS	File separator	28
BEL	bell	07		DC2	Device control 2	18		GS	Group separator	29
BS	backspace	08		DC3	Device control 3	19		RS	Record separator	30
HT	Horizontal tab	09		DC4	Device control 4	20		US	Unit separator	31
LF	Line feed	10		NAK	Negative acknowledge	21		DEL	delete	127