Table of contents

Introduction

What is ASCII?

What is UNICODE?

Difference between UNICODE and ASCII

Advantages of Using UNICODE over ASCII

Frequently Asked Questions

6.1.

How can we handle emojis and pictographs with the help of UNICODE characters?

6.2.

How do Unicode characters affect the performance of the program?

6.3.

Is UNICODE a platform-dependent encoding technique?

Conclusion

Last Updated: Mar 27, 2024

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Difference Between UNICODE and ASCII

Author Aayush Sharma

Introduction

In computers, we apply various techniques to convert our languages into machine-understandable processes. The computer is only able to understand machine language and can't understand high-level languages like C++, Java, Python, etc. We apply various character encoding techniques to convert these languages into machine language. Two of the most important methods used for character encoding are ASCII and the UNICODE technique.

In this blog, we will discuss the difference between UNICODE and ASCII. We will study ASCII and UNICODE separately and discuss some of their significant differences in a tabular format. Ultimately, we will discuss some frequently asked questions about ASCII and UNICODE.

What is ASCII?

ASCII stands for American Standard Code for Information Interchange. ASCII uses integers to encode numbers(0-9), uppercase alphabets(A-Z), lowercase alphabets(a-z), and some common symbols such as semicolon, exclamation, etc. ASCII was introduced when computers were starting to develop. Back then, computers could only understand basic symbols and letters.

Since integers are more accessible to store in the memory than letters and symbols, each character was given a unique value called ASCII value. The ASCII chart of all the numbers is shown below.

Decimal	Binary	ASCII	Decimal	Binary	ASCII
0	00000000	NUL	64	01000000	@
1	00000001	SOH	65	01000001	A
2	00000010	STX	66	01000010	B
3	00000011	ETX	67	01000011	C
4	00000100	EOT	68	01000100	D
5	00000101	ENQ	69	01000101	E
6	00000110	ACK	70	01000110	F
7	00000111	BEL	71	01000111	G
8	00001000	BS	72	01001000	H
9	00001001	HT	73	01001001	I
10	00001010	LF	74	01001010	J
11	00001011	VT	75	01001011	K
12	00001100	FF	76	01001100	L
13	00001101	CR	77	01001101	M
14	00001110	SO	78	01001110	N
15	00001111	SI	79	01001111	O
16	00010000	DLE	80	01010000	P
17	00010001	DC1	81	01010001	Q
18	00010010	DC2	82	01010010	R
19	00010011	DC3	83	01010011	S
20	00010100	DC4	84	01010100	T
21	00010101	NAK	85	01010101	U
22	00010110	SYN	86	01010110	V
23	00010111	ETB	87	01010111	X
24	00011000	CAN	88	01011000	W
25	00011001	EM	89	01011001	Y
26	00011010	SUB	90	01011010	Z
27	00011011	ESC	91	01011011	[
28	00011100	FS	92	01011100	\|
29	00011101	GS	93	01011101	]
30	00011110	RS	94	01011110	^
31	00011111	US	95	01011111	_
32	00100000	SP	96	01100000	.
33	00100001	!	97	01100001	a
34	00100010	"	98	01100010	b
35	00100011	#	99	01100011	c
36	00100100	$	100	01100100	d
37	00100101	%	101	01100101	e
38	00100110	&	102	01100110	f
39	00100111	'	103	01100111	g
40	00101000	(	104	01101000	h
41	00101001	)	105	01101001	i
42	00101010	*	106	01101010	j
43	00101011	+	107	01101011	k
44	00101100	,	108	01101100	l
45	00101101	-	109	01101101	m
46	00101110	.	110	01101110	n
47	00101111	/	111	01101111	o
48	00110000	0	112	01110000	p
49	00110001	1	113	01110001	q
50	00110010	2	114	01110010	r
51	00110011	3	115	01110011	s
52	00110100	4	116	01110100	t
53	00110101	5	117	01110101	u
54	00110110	6	118	01110110	v
55	00110111	7	119	01110111	w
56	00111000	8	120	01111000	x
57	00111001	9	121	01111001	y
58	00111010	:	122	01111010	z
59	00111011	;	123	01111011	{
60	00111100	<	124	01111100	\|
61	00111101	=	125	01111101	}
62	00111110	>	126	01111110	~
63	00111111	?	127	01111111	DEL

The primary issue while using ASCII was that it could only support 256 characters. This war was because ASCII only kept 8 bits at that time. Hence, a system that could use more bits and encode more characters was needed.

What is UNICODE?

UNICODE stands for Universal Character Set. A non-profit organization was developed called UNICODE Consortium. UNICODE can represent much more characters and symbols than the previous 8-bit ASCII. Today UNICODE is the most popular encoding scheme for encoding many characters in multiple languages.

UNICODE has multiple UTF (UNICODE Transformation Format) encoding schemes in use. These schemes are differentiated based on the number of bits they use to encode characters. The Unicode Encoding schemes include the UTF-7, UTF-8, UTF-16, and UTF-32. These schemes use 7, 8, 16, and 32 bits for encoding characters.

Difference between UNICODE and ASCII

Now that we know about both UNICODE and ASCII encoding schemes in detail, we will look at some key differences in a tabular format.

UNICODE	ASCII
UNICODE stands for Universal Character Set.	ASCII stands for American Standard Code for Information Interchange.
UNICODE supports more than a million characters.	ASCII only supports 128 characters.
UNICODE is comparatively new.	ASCII is older than UNICODE.
UNICODE has variable length encoding (7, 8, 16, and 32 bits).	ASCII has fixed-length encoding (8-bit only).
UNICODE characters require more memory.	ASCII characters acquire comparatively less memory.
UNICODE is standardized to be used in encoding in computers.	ASCII is used for electronic devices and programming languages like HTML.

Also see, Difference Between Structure and Union

Advantages of Using UNICODE over ASCII

UNICODE and ASCII are both very useful character encoding standards. But UNICODE is a more versatile and bigger character system than ASCII. Below are some of the advantages of using UNICODE over ASCII.

Bigger Character Set Size
Multiple Language Support
Supports Emojis and Symbols
Industry-wide standard for character encoding
Supports Complex Mathematical Symbols
Compatibility with old systems having ASCII

All of these above advantages make UNICODE a better choice over ASCII in todays programming scenario.

Frequently Asked Questions

How can we handle emojis and pictographs with the help of UNICODE characters?

UNICODE reserves some code points, especially for emojis and pictographs. This allows consistent representation of these visual elements across all the platforms. This makes the UNICODE character's platform independent.

How do Unicode characters affect the performance of the program?

The program requires more memory and computational power to process large UNICODE datasets. This can cause some performance issues. But these issues can be removed by hardware optimization techniques.

Is UNICODE a platform-dependent encoding technique?

UNICODE is not a platform-dependent encoding technique. UNICODE ensures consistent representation of characters across all operating systems and devices. This allows constant data exchange for the users.

Conclusion

In this article, we discussed the difference between UNICODE and ASCII. We discussed UNICODE and ASCII separately. We also discussed their critical differences in a tabular format. In the end, we concluded by discussing some frequently asked questions.

Now that you know the difference between UNICODE and ASCII, you can refer to similar articles.

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