Translations:First login - your user preferences/18/en
From LimeSurvey Manual
There is an HTML editor integrated into LimeSurvey. This tool will help you develop rich formatting for your surveys, groups, questions, and answer text; for tables, images, and so on. But as this editor takes extra space on the screen and resources on the computer, it is not always desirable to use. So you can choose between whether the HTML editor appears in-line in the browser window or whether a normal text editor is always used.