LyX is a graphical text processing system that uses the output of the typesetting system LaTeX. It combines an intuitive graphical user interface with typographic quality output.

Special features of LyX

The user interface looks at first glance similar to other graphical word processors such as Writer or Microsoft Word. However, the concept is very different.

Separation of text capture and record

In LyX document formatting takes place only at the output. First, the text can be entered without formatting. The user tells the system which function as heading, title, or Normal text he is to occupy in the finished formatted document. To output the macro language of the LaTeX typesetting program TeX is used. Therefore LyX guaranteed quality most significant sentence. In addition, particular strengths lie in the presentation of mathematical formulas and the management of footnotes and indices.

Representation when editing

When editing the document, the view is optimized for display on screen. Similar to HTML, the length of lines oriented to the width of the window and a page break occurs not on the screen. For structural elements of the document LyX pursues a strategy of WYSIWYM.

Structural elements such as headings or bulleted lists are formatted so that they are recognizable as such, but not necessarily as they appear in the printed document. For example, for the headings, an optimized for the screen font can be selected without the impact on the printed result takes.

Input via keyboard or mouse

For the recording of the document are both a graphical access via the mouse, as well as one on the keyboard is available for most elements. In particular, many commands of LaTeX syntax is automatically detected and converted into an appropriate graphical representation.

Unrecognized commands are passed unchanged to LaTeX on the issue. In this way it is possible to use all possibilities of LaTeX. In the editing window, these commands are displayed in red. This display runs counter to the project objective, indicate no command in the editor. This developed into project- internal, half-jokingly, the term Evil Red Text, evil red text, abbreviated ERT.


LyX was developed by the former computer science student Ettrich as part of his study working with the GUI toolkit Motif 1995. When he was looking after the trial work on the Internet for collaborators to develop LyX together, he realized that had little experience or access to Motif. Therefore, he looked for a new, free GUI toolkit. The choice finally fell on the XForms toolkit. In later years, the Independence GUI framework has been introduced in order to achieve that, besides XForms also other GUI toolkits (Qt, Gtk ) can be used. In current versions, only the Qt GUI toolkit is supported.