Unicode has symbols to represent ASCII unprintable characters.
| Decimal | Hex | Abbr | Unicode Symbol | Caret Notation | C Escape Syntax | Description |
|---|---|---|---|---|---|---|
| 0 | 00 | NUL | ␀ | ^@ | \0 | Null character |
| 1 | 01 | SOH | ␁ | ^A | Start of Header | |
| 2 | 02 | STX | ␂ | ^B | Start of Text | |
| 3 | 03 | ETX | ␃ | ^C | End of Text | |
| 4 | 04 | EOT | ␄ | ^D | End of Transmission | |
| 5 | 05 | ENQ | ␅ | ^E | Enquiry | |
| 6 | 06 | ACK | ␆ | ^F | Acknowledgment | |
| 7 | 07 | BEL | ␇ | ^G | \a | Bell |
| 8 | 08 | BS | ␈ | ^H | \b | Backspace |
| 9 | 09 | HT | ␉ | ^I | \t | Horizontal Tab |
| 10 | 0A | LF | ␊ | ^J | \n | Line feed |
| 11 | 0B | VT | ␋ | ^K | \v | Vertical Tab |
| 12 | 0C | FF | ␌ | ^L | \f | Form feed |
| 13 | 0D | CR | ␍ | ^M | \r | Carriage return |
| 14 | 0E | SO | ␎ | ^N | Shift Out | |
| 15 | 0F | SI | ␏ | ^O | Shift In | |
| 16 | 10 | DLE | ␐ | ^P | Data Link Escape | |
| 17 | 11 | DC1 | ␑ | ^Q | Device Control 1 (oft. XON) | |
| 18 | 12 | DC2 | ␒ | ^R | Device Control 2 | |
| 19 | 13 | DC3 | ␓ | ^S | Device Control 3 (oft. XOFF) | |
| 20 | 14 | DC4 | ␔ | ^T | Device Control 4 | |
| 21 | 15 | NAK | ␕ | ^U | Negative Acknowledgment | |
| 22 | 16 | SYN | ␖ | ^V | Synchronous Idle | |
| 23 | 17 | ETB | ␗ | ^W | End of Trans. Block | |
| 24 | 18 | CAN | ␘ | ^X | Cancel | |
| 25 | 19 | EM | ␙ | ^Y | End of Medium | |
| 26 | 1A | SUB | ␚ | ^Z | Substitute | |
| 27 | 1B | ESC | ␛ | ^[ | \e | Escape |
| 28 | 1C | FS | ␜ | ^\ | File Separator | |
| 29 | 1D | GS | ␝ | ^] | Group Separator | |
| 30 | 1E | RS | ␞ | ^^ | Record Separator | |
| 31 | 1F | US | ␟ | ^_ | Unit Separator | |
| 127 | 7F | DEL | ␡ | ^? | Delete | |
| Decimal | Hex | Abbr | Unicode Symbol | Caret Notation | C Escape Code | Description |
Note that the caret notation is heavily used in emacs. Emacs: Newline Representations ^M ^J ^L.
Non-printable ASCII is also heavily used in unix terminal. See: Linux: Terminal Control Sequence Keys (tty, stty) ⌨
On Linux, you can view ASCII table by man ascii.
Here are other character representation symbols. They are often used in text editor or word processor to indicate whitespace.
Tab ↹ ⇄ ⇤ ⇥ ↤ ↦ ◁ ▷
space · ␣ ˽ ␠ ␢
paragraph, section, newline. ¶ §  ↵ ↩ ⏎
misc: ␁ ␂
placeholder, replacement: �
Sample usage: Emacs's whitespace-mode
Unicode: Keyboard Symbols ⌘ ⏎ ↹ ⌫ ❖ ⇞ ⇟
ƒ ␥ ␦
Misc icons ⌗
Misc ⌜ ⌝ ⌞ ⌟ ⎔ ⎖ ⎁ ⎂ ⎃ ⎄ ⎅
checkmarks ✓ ✔ ✗ ✘ ☐ ☑ ☒ 𐄂 ⍻ ❍ ❏ ❐ ❑ ❒
⑀ ⑁ ⑂ ⑃ ⑄ ⑅ ⑆ ⑇ ⑈ ⑉ ⑊