UTF-8 ](/en-US/docs/Glossary/UTF-8)
    516. [ UUID ](/en-US/docs/Glossary/UUID)
    517. [ UX ](/en-US/docs/Glossary/UX)
    518. [ Validator ](/en-US/docs/Glossary/Validator)
    519. [ Value ](/en-US/docs/Glossary/Value)
    520. [ Variable ](/en-US/docs/Glossary/Variable)
    521. [ Vendor Prefix ](/en-US/docs/Glossary/Vendor_Prefix)
    522. [ Viewport ](/en-US/docs/Glossary/Viewport)
    523. [ Visual Viewport ](/en-US/docs/Glossary/Visual_Viewport)
    524. [ Void element ](/en-US/docs/Glossary/Void_element)
    525. [ VoIP ](/en-US/docs/Glossary/VoIP)
    526. [ W3C ](/en-US/docs/Glossary/W3C)
    527. [ WAI ](/en-US/docs/Glossary/WAI)
    528. [ WCAG ](/en-US/docs/Glossary/WCAG)
    529. [ Web performance ](/en-US/docs/Glossary/Web_performance)
    530. [ Web server ](/en-US/docs/Glossary/Web_server)
    531. [ Web standards ](/en-US/docs/Glossary/Web_standards)
    532. [ WebAssembly ](/en-US/docs/Glossary/WebAssembly)
    533. [ WebDAV ](/en-US/docs/Glossary/WebDAV)
    534. [ WebExtensions ](/en-US/docs/Glossary/WebExtensions)
    535. [ WebGL ](/en-US/docs/Glossary/WebGL)
    536. [ WebIDL ](/en-US/docs/Glossary/WebIDL)
    537. [ WebKit ](/en-US/docs/Glossary/WebKit)
    538. [ WebM ](/en-US/docs/Glossary/WebM)
    539. [ WebP ](/en-US/docs/Glossary/WebP)
    540. [ WebRTC ](/en-US/docs/Glossary/WebRTC)
    541. [ WebSockets ](/en-US/docs/Glossary/WebSockets)
    542. [ WebVTT ](/en-US/docs/Glossary/WebVTT)
    543. [ WHATWG ](/en-US/docs/Glossary/WHATWG)
    544. [ Whitespace ](/en-US/docs/Glossary/Whitespace)
    545. [ WindowProxy ](/en-US/docs/Glossary/WindowProxy)
    546. [ World Wide Web ](/en-US/docs/Glossary/World_Wide_Web)
    547. [ Wrapper ](/en-US/docs/Glossary/Wrapper)
    548. [ XForms ](/en-US/docs/Glossary/XForms) Deprecated 
    549. [ XHTML ](/en-US/docs/Glossary/XHTML)
    550. [ XInclude ](/en-US/docs/Glossary/XInclude)
    551. [ XLink ](/en-US/docs/Glossary/XLink)
    552. [ XML ](/en-US/docs/Glossary/XML)
    553. [ XMLHttpRequest (XHR) ](/en-US/docs/Glossary/XMLHttpRequest)
    554. [ XPath ](/en-US/docs/Glossary/XPath)
    555. [ XQuery ](/en-US/docs/Glossary/XQuery)
    556. [ XSLT ](/en-US/docs/Glossary/XSLT)
    557. [ Zstandard compression ](/en-US/docs/Glossary/Zstandard_compression)

##  In this article

  * See also 

#  ASCII

**ASCII** ( _American Standard Code for Information Interchange_ ) is a
character encoding standard of 128 7-bit used by computers for converting
letters, numbers, punctuation, and control codes into digital form.

The first 33 ASCII code points are non-printing control codes including the
carriage return, line feed, tab, and several obsolete non-printable codes
stemming from its origin of representing telegraph codes. The other 95 are
printable characters, including digits (0-9), lowercase (a-z) and uppercase
(A-Z) letters, and punctuation symbols.

Many computer systems instead use [ Unicode ](/en-US/docs/Glossary/Unicode) ,
which has millions of code points, but the first 128 of these are the same as
the ASCII set. [ UTF-8 ](/en-US/docs/Glossary/UTF-8) superseded ASCII on the
Web in 2007.

##  See also

  * [ ASCII ](https://en.wikipedia.org/wiki/ASCII) on Wikipedia 

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