: Unicode character recognition.

Unicode character information

Plus-minus sign

Displayed on your computer as: ±
(if the character is not rendered properly, you may not have the appropriate fonts)

Unicode name: Plus-minus sign
Alternative names: Codepoint (hexadecimal): 0x00B1
Codepoint (decimal): 177
In unicode block: Latin-1 Supplement

Html entities:

± or ± or ±

Character input:

There is no universal input system for Unicode characters. But you can use the system specific input methods below.

WindowsHold down Alt and press + on the numeric keyboard. Type: 00B1 and release Alt. A registry key needs to be enabled for this to work. See Unicode input (wikipedia) for more details.
Linux: Hold down Crtl and ⇧ Shift and type U00B1. Now press ↵ Enter and release Crtl and ⇧ Shift.

Other Infos:

General category: Sm (Math_Symbol): A symbol of primarily mathematical use.
Bidirectional class is: ET (European_Terminator): A terminator in a numeric format context, includes currency signs.
Canocial combining class is: 0 (Not_Reordered): Spacing and enclosing marks; also many vowel and consonant signs, even if nonspacing.