A method to control a virtual reality display unit, comprising the steps: - track (step I) the environment of a space surrounding the virtual reality display unit, - automatically identify and separate (step II) real-world objects (2, 2a, 2b, 2c, 2d, 2e) of the tracked environment by forming virtual objects (V, V1, V2, V3, V4, V5, V6, V7) and providing individual identification labels (L, L1, L2, L3, L4, L5) to the virtual objects (V, V1, V2, V3, V4, V5, V6, V7), - classify (step III) the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) together with their individual identification labels (L, L1, L2, L3, L4, L5) into an object-library, - marking (step IV) a number of virtual objects (V, V1, V2, V3, V4, V5, V6, V7), by a user of the virtual reality display unit and/or automatically, by linking an individual relevance-marker with each virtual object (V, V1, V2, V3, V4, V5, V6, V7), wherein the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) are marked with relevance-markers, wherein a relevance of each virtual object (V, V1, V2, V3, V4, V5, V6, V7) can be derived directly from its relevance-marker, - displaying (step V) the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) of the object-library by the virtual reality display unit dependent on relevance-markers, wherein a surrounding "real world" is invisible to the user, characterised in that the relevance-marker for each virtual object has more than two possible states, in that in the displaying (step V) the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) of the object-library are shown by the virtual reality display unit in different shapes or not at all dependent on their relevance, and in that a virtual object (V, V1, V2, V3, V4, V5, V6, V7) is not shown if its relevance lies under a predefined value, the virtual object (V, V1, V2, V3, V4, V5, V6, V7) is shown with a predefined texture if its relevance lies between a first range of values, and the virtual object (V, V1, V2, V3, V4, V5, V6, V7) is shown as image of the real-world object if its relevance lies between a second range of values. - track (step I) the environment of a space surrounding the virtual reality display unit, - automatically identify and separate (step II) real-world objects (2, 2a, 2b, 2c, 2d, 2e) of the tracked environment by forming virtual objects (V, V1, V2, V3, V4, V5, V6, V7) and providing individual identification labels (L, L1, L2, L3, L4, L5) to the virtual objects (V, V1, V2, V3, V4, V5, V6, V7), - classify (step III) the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) together with their individual identification labels (L, L1, L2, L3, L4, L5) into an object-library, - marking (step IV) a number of virtual objects (V, V1, V2, V3, V4, V5, V6, V7), by a user of the virtual reality display unit and/or automatically, by linking an individual relevance-marker with each virtual object (V, V1, V2, V3, V4, V5, V6, V7), wherein the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) are marked with relevance-markers, wherein a relevance of each virtual object (V, V1, V2, V3, V4, V5, V6, V7) can be derived directly from its relevance-marker, - displaying (step V) the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) of the object-library by the virtual reality display unit dependent on relevance-markers, wherein a surrounding "real world" is invisible to the user, characterised in that the relevance-marker for each virtual object has more than two possible states, in that in the displaying (step V) the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) of the object-library are shown by the virtual reality display unit in different shapes or not at all dependent on their relevance, and in that a virtual object (V, V1, V2, V3, V4, V5, V6, V7) is not shown if its relevance lies under a predefined value, the virtual object (V, V1, V2, V3, V4, V5, V6, V7) is shown with a predefined texture if its relevance lies between a first range of values, and the virtual object (V, V1, V2, V3, V4, V5, V6, V7) is shown as image of the real-world object if its relevance lies between a second range of values. wherein a surrounding "real world" is invisible to the user, characterised in that the relevance-marker for each virtual object has more than two possible states, in that in the displaying (step V) the virtual objects (V, V1, V2, V3, V4, V5, V6, V7) of the object-library are shown by the virtual reality display unit in different shapes or not at all dependent on their relevance, and in that a virtual object (V, V1, V2, V3, V4, V5, V6, V7) is not shown if its relevance lies under a predefined value, the virtual object (V, V1, V2, V3, V4, V5, V6, V7) is shown with a predefined texture if its relevance lies between a first range of values, and the virtual object (V, V1, V2, V3, V4, V5, V6, V7) is shown as image of the real-world object if its relevance lies between a second range of values.