Until recently, heavy use of system tags would have caused such tags to appear in your post lists and in your tag cloud - often larger than other tags due to frequent use. We believe, that tag clouds should represent you and your interests rather than your habits. Therefore, several system tags are now hidden from both, tag cloud and post lists. As an example see the two tag clouds below.
The first one is the old version where no system tags are hidden, while the second one is what the cloud currently looks like. In the new cloud, the system tags
- sent:anton (indicating that posts were sent to user anton) and
- sys:relevantFor:kde (meaning a that posts were marked relevant for the group kde)
In post lists (like on the home page or user post lists) hidden system tags are generally not displayed. However, on your own posts - if tagged with hidden system tags - you will find a small cog wheel symbol like here:
Happy (system) tagging!