Orca
Orca is a free, open source, flexible, and extensible screen reader that provides access to the graphical desktop via user-customizable combinations of speech and/or braille.
Orca works with applications and toolkits that support the assistive technology service provider interface (AT-SPI), which is the primary assistive technology infrastructure for Unix-like environments like Linux, OpenBSD or Solaris. Applications and toolkits supporting the AT-SPI include the GNOME GTK+ toolkit, the Java platform’s Swing toolkit, SWT, OpenOffice/LibreOffice, Mozilla, and WebKitGtk. AT-SPI support for the KDE Qt toolkit is currently being pursued.
Thanks to the generous contributions of volunteers on the GNOME Translation Teams, Orca has been translated into many of the world’s languages, with support for additional languages being added every day.