Letter X
| X | 7 projects |
| X app | 2 projects |
| X Font Protocol | 1 project |
| X Window | 5 projects |
| X Window System | 4 projects |
| X windows | 4 projects |
| X.509 | 2 projects |
| X10 | 4 projects |
| X11 | 63 projects |
| X11 libs only | 3 projects |
| X11 Tools | 3 projects |
| X11-windows system | 3 projects |
| X11/Motif | 1 project |
| X12 | 1 project |
| X3D | 2 projects |
| X509 | 1 project |
| x86 | 7 projects |
| x86-64 | 3 projects |
| XA Specification | 1 project |
| XA Transaction Manager | 1 project |
| xalan | 1 project |
| xamp | 2 projects |
| Xampp | 4 projects |
| Xapian | 4 projects |
| xapp | 1 project |
| Xataface | 2 projects |
| xbase | 1 project |
| xbmc | 3 projects |
| XBMC Mozart | 1 project |
| xboard | 1 project |
| XboX | 2 projects |
| xBSD | 1 project |
| XCB | 1 project |
| xchat | 1 project |
| xcode | 3 projects |
| Xcode IDE | 1 project |
| xdcc | 3 projects |
| XDMCP | 1 project |
| Xen | 8 projects |
| XenServer | 2 projects |
| Xerces | 2 projects |
| XEvIE | 1 project |
| XFCE | 17 projects |
| xfce4 | 3 projects |
| XFN | 1 project |
| XForms | 5 projects |
| Xhosa | 3 projects |
| XHTML | 65 projects |
| xilinx | 2 projects |
| Xilinx EDK | 1 project |
| xinclude | 1 project |
| xinelib | 1 project |
| xlayers | 1 project |
| xlib | 15 projects |
| XLIFF | 2 projects |
| xls | 2 projects |
| XLST | 1 project |
| xlsx | 3 projects |
| xm | 1 project |
| XMD5 | 1 project |
| XML | 878 projects |
| XML Data Storage | 1 project |
| XML Database XQuery XPath | 1 project |
| XML Editing | 1 project |
| xml output | 1 project |
| XML parsing | 1 project |
| XML Schema | 20 projects |
| XML validation | 2 projects |
| XML-GrammarBase | 1 project |
| XML-LibXML | 4 projects |
| xml-light | 2 projects |
| XML-RPC | 19 projects |
| xml2rfc | 1 project |
| XML::Writer | 1 project |
| XMLBeans | 5 projects |
| XMLHttpRequest | 2 projects |
| xmlrpc | 6 projects |
| xmlrpc client | 5 projects |
| xmlrpc-c | 1 project |
| XMLRPC::Lite | 1 project |
| xmlsec | 1 project |
| xmlstarlet | 1 project |
| XMLTV | 2 projects |
| xmms2 | 1 project |
| Xmodem | 1 project |
| xmodmap | 1 project |
| xmpp | 33 projects |
| XOM | 1 project |
| XOOPS CMS | 1 project |
| XOR | 1 project |
| Xorg | 2 projects |
| xosd | 1 project |
| XP | 4 projects |
| xpath | 21 projects |
| XPath2 | 2 projects |
| XPCOM | 3 projects |
| XPDL | 3 projects |
| xpm | 1 project |
| Xpra | 1 project |
| XPRISO | 1 project |
