ASCII control characters (character code 0-31)

The first 32 characters in the ASCII-table are unprintable control codes and are used to control peripherals such as printers.
DEC OCT HEX BIN Symbol HTML Number HTML Name Description
00000000000000NUL� Null char
10010100000001SOH Start of Heading
20020200000010STX Start of Text
30030300000011ETX End of Text
40040400000100EOT End of Transmission
50050500000101ENQ Enquiry
60060600000110ACK Acknowledgment
70070700000111BEL Bell
80100800001000 BS Back Space
90110900001001 HT	 Horizontal Tab
100120A00001010 LF
 Line Feed
110130B00001011 VT Vertical Tab
120140C00001100 FF Form Feed
130150D00001101 CR
 Carriage Return
140160E00001110 SO Shift Out / X-On
150170F00001111 SI Shift In / X-Off
160201000010000DLE Data Line Escape
170211100010001DC1 Device Control 1 (oft. XON)
180221200010010DC2 Device Control 2
190231300010011DC3 Device Control 3 (oft. XOFF)
200241400010100DC4 Device Control 4
210251500010101NAK Negative Acknowledgement
220261600010110SYN Synchronous Idle
230271700010111ETB End of Transmit Block
240301800011000CAN Cancel
250311900011001 EM End of Medium
260321A00011010SUB Substitute
270331B00011011ESC Escape
280341C00011100 FS File Separator
290351D00011101 GS Group Separator
300361E00011110 RS Record Separator
310371F00011111 US Unit Separator

ASCII printable characters (character code 32-127)

Codes 32-127 are common for all the different variations of the ASCII table, they are called printable characters, represent letters, digits, punctuation marks, and a few miscellaneous symbols. You will find almost every character on your keyboard. Character 127 represents the command DEL.
DEC OCT HEX BIN Symbol HTML Number HTML Name Description
320402000100000   Space
330412100100001!! Exclamation mark
340422200100010"""Double quotes (or speech marks)
350432300100011## Number
360442400100100$$ Dollar
370452500100101%% Procenttecken
380462600100110&&&Ampersand
390472700100111'' Single quote
400502800101000(( Open parenthesis (or open bracket)
410512900101001)) Close parenthesis (or close bracket)
420522A00101010** Asterisk
430532B00101011++ Plus
440542C00101100,, Comma
450552D00101101-- Hyphen
460562E00101110.. Period, dot or full stop
470572F00101111// Slash or divide
48060300011000000 Zero
49061310011000111 One
50062320011001022 Two
51063330011001133 Three
52064340011010044 Four
53065350011010155 Five
54066360011011066 Six
55067370011011177 Seven
56070380011100088 Eight
57071390011100199 Nine
580723A00111010:: Colon
590733B00111011;&#59; Semicolon
600743C00111100<&#60;&lt;Less than (or open angled bracket)
610753D00111101=&#61; Equals
620763E00111110>&#62;&gt;Greater than (or close angled bracket)
630773F00111111?&#63; Question mark
641004001000000@&#64; At symbol
651014101000001A&#65; Uppercase A
661024201000010B&#66; Uppercase B
671034301000011C&#67; Uppercase C
681044401000100D&#68; Uppercase D
691054501000101E&#69; Uppercase E
701064601000110F&#70; Uppercase F
711074701000111G&#71; Uppercase G
721104801001000H&#72; Uppercase H
731114901001001I&#73; Uppercase I
741124A01001010J&#74; Uppercase J
751134B01001011K&#75; Uppercase K
761144C01001100L&#76; Uppercase L
771154D01001101M&#77; Uppercase M
781164E01001110N&#78; Uppercase N
791174F01001111O&#79; Uppercase O
801205001010000P&#80; Uppercase P
811215101010001Q&#81; Uppercase Q
821225201010010R&#82; Uppercase R
831235301010011S&#83; Uppercase S
841245401010100T&#84; Uppercase T
851255501010101U&#85; Uppercase U
861265601010110V&#86; Uppercase V
871275701010111W&#87; Uppercase W
881305801011000X&#88; Uppercase X
891315901011001Y&#89; Uppercase Y
901325A01011010Z&#90; Uppercase Z
911335B01011011[&#91; Opening bracket
921345C01011100\&#92; Backslash
931355D01011101]&#93; Closing bracket
941365E01011110^&#94; Caret - circumflex
951375F01011111_&#95; Underscore
961406001100000`&#96; Grave accent
971416101100001a&#97; Lowercase a
981426201100010b&#98; Lowercase b
991436301100011c&#99; Lowercase c
1001446401100100d&#100; Lowercase d
1011456501100101e&#101; Lowercase e
1021466601100110f&#102; Lowercase f
1031476701100111g&#103; Lowercase g
1041506801101000h&#104; Lowercase h
1051516901101001i&#105; Lowercase i
1061526A01101010j&#106; Lowercase j
1071536B01101011k&#107; Lowercase k
1081546C01101100l&#108; Lowercase l
1091556D01101101m&#109; Lowercase m
1101566E01101110n&#110; Lowercase n
1111576F01101111o&#111; Lowercase o
1121607001110000p&#112; Lowercase p
1131617101110001q&#113; Lowercase q
1141627201110010r&#114; Lowercase r
1151637301110011s&#115; Lowercase s
1161647401110100t&#116; Lowercase t
1171657501110101u&#117; Lowercase u
1181667601110110v&#118; Lowercase v
1191677701110111w&#119; Lowercase w
1201707801111000x&#120; Lowercase x
1211717901111001y&#121; Lowercase y
1221727A01111010z&#122; Lowercase z
1231737B01111011{&#123; Opening brace
1241747C01111100|&#124; Vertical bar
1251757D01111101}&#125; Closing brace
1261767E01111110~&#126; Equivalency sign - tilde
1271777F01111111&#127; Delete

ASCII on Wikipedia
American National Standards Institute
ASCII Art Collection