Difference Between UNICODE and ASCII

Learn via video course
FREE
View all courses
C++ Course: Learn the Essentials
C++ Course: Learn the Essentials
by Prateek Narang
1000
5
Start Learning
C++ Course: Learn the Essentials
C++ Course: Learn the Essentials
by Prateek Narang
1000
5
Start Learning

Overview

Encoding schemes are used to convert characters we use daily to machine language. The characters can be emojis, alphabets, Greek symbols, etc.

ASCII and Unicode are two popular encoding schemes. ASCII encodes symbols, digits, letters, etc., whereas Unicode encodes special texts from different languages, letters, symbols, etc.

It can be said that ASCII is a subset of the Unicode encoding scheme. Below we will be studying the difference between Unicode and ASCII.

The ASCII Characters

Now, we will be discussing what ASCII characters are. ASCII stands for American Standard Code for Information Interchange and is used for electronic communication.

It uses integers to encode numbers(0-9), uppercase alphabets(A-Z), lowercase alphabets(a-z) and symbols such as semicolon(;), exclamation(!) etc. Integers are easy to store in electronic devices rather than alphabets or symbols. For example, 97 is used to represent "a", and 33 is used to represent "!" and can be easily stored in memory.

If the ASCII value of a particular alphabet is known, then the ASCII value of another alphabet can be estimated. For example, ASCII value of a is 97, then the ASCII value of z will be 97+25=12297+25=122.

ASCII uses 8 bits to encode any character, most of them from the English language used in modern-day programming. It is also used in graphic arts to represent clip art or images using characters.

The major disadvantage of ASCII is that it can represent only 256 different characters as it can use only 8 bits. ASCII cannot be used to encode the many types of characters found around the world. Unicode was extended further to UTF-16 and UTF-32 to encode the various types of characters. Therefore, the significant difference between ASCII and Unicode is the number of bits used to encode.

Decimal-Binary-ASCII conversion chart

DecimalBinaryASCIIDecimalBinaryASCII
000000000NUL6401000000@
100000001SOH6501000001A
200000010STX6601000010B
300000011ETX6701000011C
400000100EOT6801000100D
500000101ENQ6901000101E
600000110ACK7001000110F
700000111BEL7101000111G
800001000BS7201001000H
900001001HT7301001001I
1000001010LF7401001010J
1100001011VT7501001011K
1200001100FF7601001100L
1300001101CR7701001101M
1400001110SO7801001110N
1500001111SI7901001111O
1600010000DLE8001010000P
1700010001DC18101010001Q
1800010010DC28201010010R
1900010011DC38301010011S
2000010100DC48401010100T
2100010101NAK8501010101U
2200010110SYN8601010110V
2300010111ETB8701010111X
2400011000CAN8801011000W
2500011001EM8901011001Y
2600011010SUB9001011010Z
2700011011ESC9101011011[
2800011100FS9201011100|
2900011101GS9301011101]
3000011110RS9401011110^
3100011111US9501011111_
3200100000SP9601100000.
3300100001!9701100001a
3400100010"9801100010b
3500100011#9901100011c
3600100100$10001100100d
3700100101%10101100101e
3800100110&10201100110f
3900100111'10301100111g
4000101000(10401101000h
4100101001)10501101001i
4200101010*10601101010j
4300101011+10701101011k
4400101100,10801101100l
4500101101-10901101101m
4600101110.11001101110n
4700101111/11101101111o
4800110000011201110000p
4900110001111301110001q
5000110010211401110010r
5100110011311501110011s
5200110100411601110100t
5300110101511701110101u
5400110110611801110110v
5500110111711901110111w
5600111000812001111000x
5700111001912101111001y
5800111010:12201111010z
5900111011;12301111011{
6000111100<12401111100|
6100111101=12501111101}
6200111110>12601111110~
6300111111?12701111111DEL

The Unicode Characters

Unicode stands for Universal Character Set and is maintained by Unicode Consortium. Unicode Consortium is a non-profit corporation that sets the standards for software to be used internationally. The IT industry standardizes Unicode to encode and represent characters in computers and other electronic and communication devices.

unicode generater

Unicode represents a vast ocean of characters, formulas, mathematical symbols, and texts from different languages such as Devanagiri, Latin, Greek, Cyrillic, Armenian, etc. Unicode is also used to represent texts written from right to left, such as Hebrew and Arabic. Unicode is one of the only encoding schemes that can be used to encode many of the characters used around the world.

Unicode Transformation Format(UTF) is the type of Unicode encoding scheme. Unicode encoding schemes are classified based on the number of bits used to encode the characters. The types of Unicode encoding schemes used at present are UTF-7, UTF-8, UTF-16, and UTF-32 using 7 bits, 8 bits, 16 bits, and 32 bits, respectively, for representing characters. The requirement of Unicode is for the internationalization and localization of computer software and is also used for the operating system, XML, Java programming, etc.

Relationship Between ASCII And Unicode

Unicode has several encoding formats, two of which are UTF-7 and UTF-8, which use 7 bits and 8 bits, respectively, to represent characters that are otherwise difficult to store in memory. ASCII also uses 7 and 8 bits for the representation of characters. A large number of characters used around the world which cannot be encoded by using 8-bit representation led to the creation of UTF-16 and UTF-32 encoding formats under Unicode encoding. Thus, ASCII is a subset of the Unicode encoding scheme.

Difference Between ASCII And Unicode

ParameterUnicodeASCII
AbbreviationUnicode stands for Universal Character Set.ASCII stands for American Standard Code for Information Interchange.
UsageUnicode is standardized by the IT industry to be used in encoding and representing characters in computers.ASCII is used for electronic communication and in programming languages such as HTML.
Characters representedUnicode is used to represent a large number of characters, formulas, mathematical symbols, and texts from different languages such as Devanagiri, Latin, Greek, Cyrillic, Armenian, etc.ASCII is used to represent English Alphabets, digits, some mathematical symbols(+,-,/ etc.) and grammatical symbols such as punctuation, exclamation, etc.
Bits used for encodingUnicode uses four type of encoding formats, i.e, UTF-7, UTF-8, UTF-16, UTF-32 utilising 7,8,16 and 32 bits respectively.ASCII only uses 7 or 8 bits to represent various characters.
Memory occupiedUnicode's UTF-8, UTF-16, and UTF-32 encoding schemes use 8, 16, and 32 bits, respectively, thus consuming more memory.ASCII uses 7 or 8 bits in encoding; therefore, it occupies less space in memory.

Become a coding superstar with our Free C++ course. Enroll today and lead the way in coding innovation.

Conclusion

  • Characters such as emojis, complex mathematical symbols, etc., are mapped to the bits by encoding schemes such as ASCII and Unicode to be stored in memory.
  • ASCII encodes very basic day-to-day characters such as alphabets, numbers, etc., with its 7 to 8-bit encoding hence consuming less space.
  • Unicode has many formats and thus is a very flexible encoding scheme that is standardized for operating systems,.NET frameworks, Java, etc.
  • ASCII occupies less space, making it perfect for electronic communication, such as sending text messages.
  • The difference between Unicode and ASCII is basically due to the number of bits they use and amount of characters they can encode.
  • ASCII is a subset of Unicode as Unicode represents many other characters along with characters represented by ASCII.

See Also: