The timetable card represents one block of teaching in the timetable (one "window" in the timetable, most often two hours long). It contains the course code (according to the Study plans = White Book), the surname of the teacher and the code of the classroom. The timetable card is colored according to the department that provides the relevant course.
Most courses have lectures and exercises, so they have several timetable cards in the timetable (there is usually a noticeable difference in the name of the timetable card: e.g. "LAL" is a lecture and "LALcv" is an exercise).
An example of the timetable card with explanations is in the picture:
The White Book is the basis for creating a timetable for a given semester, as it contains the study plans of all study programs in all years of bachelor's or master's study.
The White Book is published annually and you can find it in PDF on the FNSPE website (For students → Study Programmes and Regulations).
If the course code is highlighted in red, the course is realised in a non-standard way. For example: once every 14 days OR only for a certain part of the semester OR there is an alternation of two courses in one classroom with a weekly frequency...
You can find specific information about the implementation of such a course in the important information or the relevant teacher will provide it to you at the first lecture/exercise.