I found a tag called "r". I don't know what it's used for. Can we all make a description for the tags that you created? That way we can use it properly.
No, we should not create descriptions for tags like r. This was a typo tag created when a user typed "gramma r" instead of "grammar". I removed it from the question and retagged it. It has no tag wiki, so it'll be automatically removed by the system shortly. If it had a tag wiki, it would be needlessly kept around.