Complex Text Layout languages (frequently referred to as CTL languages) are languages whose writing systems require complex transformations between text input and text display for proper rendering on the screen or the printed page. In other words, for these languages there may be a difference between the way text is stored and the way it is displayed. The term is used in the field of software internationalization.

Examples of CTL languages are Arabic, Hebrew, Hindi, and Thai.

The main characteristics of CTL language complexity are:

• Bi-directional text, where characters may be written from either right-to-left or left-to-right direction.
• Context-sensitive shaping , where character may changes its shape, depends on its location and/or surrounding characters. For example, a character in Arabic script can have four different shape forms, depending on context.

See also

• CJK
• Unicode
• Typography

External Links

• Complex Text Layout - The Open Group's Desktop Technologies
• Supporting Indic Scripts in Mozilla, also other CTL scripts
• CTL Architecture in Solaris - Solaris Globalization Whitepapers
• Complex Scripts - Microsoft Global Development and Computing Portal
• Theppitak's Homepage - information about Thai language processing