ascii - the ASCII character set encoded in octal, decimal, and hexadecimal
ASCII is the American Standard Code for Information Interchange. It is a 7-bit code. Many 8-bit codes (such as ISO 8859-1, the Linux default character set) contain ASCII as their lower half. The international counterpart of ASCII is known as ISO 646.
The following table contains the 128 ASCII characters.
C program '\X' escapes are noted.
|Oct|Dec|Hex|Char| |Oct|Dec|Hex|Char |000|0|00|NUL '\0' (Null)| |100|64|40|@ |001|1|01|SOH (Start heading)| |101|65|41|A |002|2|02|STX (Start text)| |102|66|42|B |003|3|03|ETX (End text)| |103|67|43|C |004|4|04|EOT (End of transmission)| |104|68|44|D |005|5|05|ENQ (Enquiry)| |105|69|45|E |006|6|06|ACK (Acknowledge)| |106|70|46|F |007|7|07|BEL '\a' (ring bell)| |107|71|47|G |010|8|08|BS '\b' (backspace)| |110|72|48|H |011|9|09|HT '\t' (horizontal tab)| |111|73|49|I |012|10|0A|LF '\n' (line feed)| |112|74|4A|J |013|11|0B|VT '\v' (vertical tab)| |113|75|4B|K |014|12|0C|FF '\f' (form feed)| |114|76|4C|L |015|13|0D|CR '\r' (carriage return)| |115|77|4D|M |016|14|0E|SO (shift out)| |116|78|4E|N |017|15|0F|SI (shift in)| |117|79|4F|O |020|16|10|DLE (data link escape)| |120|80|50|P |021|17|11|DC1 (device control 1)| |121|81|51|Q |022|18|12|DC2 (dev. cntl 2)| |122|82|52|R |023|19|13|DC3 (dev. cntl 3)| |123|83|53|S |024|20|14|DC4 (dev. cntl 4)| |124|84|54|T |025|21|15|NAK (negative acknowledge)| |125|85|55|U |026|22|16|SYN (synchronous idle)| |126|86|56|V |027|23|17|ETB (end of transmission block)| |127|87|57|W |030|24|18|CAN (cancel)| |130|88|58|X |031|25|19|EM (end of medium)| |131|89|59|Y |032|26|1A|SUB (substitute)| |132|90|5A|Z |033|27|1B|ESC (escape)| |133|91|5B||034|28|1C|FS (file separator)| |134|92|5C|\? |036|30|1E|RS (record separator)| |136|94|5E|^^ |037|31|1F|US (unit separator)| |137|95|5F|_ |040|32|20|SPACE| |140|96|60|` |041|33|21|!| |141|97|61|a |042|34|22|"| |142|98|62|b |043|35|23|#| |143|99|63|c |044|36|24|$| |144|100|64|d |045|37|25|%| |145|101|65|e |046|38|26|&| |146|102|66|f |047|39|27|'| |147|103|67|g |050|40|28|(| |150|104|68|h |051|41|29|)| |151|105|69|i |052|42|2A|*| |152|106|6A|j |053|43|2B|+| |153|107|6B|k |054|44|2C|,| |154|108|6C|l |055|45|2D|-| |155|109|6D|m |056|46|2E|.| |156|110|6E|n |057|47|2F|/| |157|111|6F|o |060|48|30|0| |160|112|70|p |061|49|31|1| |161|113|71|q |062|50|32|2| |162|114|72|r |063|51|33|3| |163|115|73|s |064|52|34|4| |164|116|74|t |065|53|35|5| |165|117|75|u |066|54|36|6| |166|118|76| v |067|55|37|7| |167|119|77|w |070|56|38|8| |170|120|78|x |071|57|39|9| |171|121|79|y |072|58|3A|:| |172|122|7A|z |073|59|3B|;| |173|123|7B|{ |074|60|3C|<| |174|124|7C| vertical bar |075|61|3D|=| |175|125|7D|} |076|62|3E|>| |176|126|7E| |077|63|3F|?| |177|127|7F|DEL
An ascii manual page appeared in Version 7 AT&T UNIX.
On older terminals, the underscore code is displayed as a left arrow, called backarrow, the caret is displayed as an up-arrow and the vertical bar has a hole in the middle.
Uppercase and lowercase characters differ by just one bit and the ASCII character 2 differs from the double quote by just one bit, too. That made it much easier to encode characters mechanically or with a non-microcontroller-based electronic keyboard and that pairing was found on old teletypes.
The ASCII standard was published by the United States of America Standards Institute (USASI) in 1968.
iso_8859_1(7), iso_8859_15(7), iso_8859_7(7)
See also the utf8(7) man page.
34 pages link to ascii(7):
