You can gift subs to viewers but at the moment you can't gift bits to fellow viewers. People who receive gifted bits can then use them to cheer their favourite streamers, or if they are already a streamer they can keep them for themselves. As an example sometimes there may have been someone generous who may have just gifted a load of subs to the community that in turn you may want to tip them some bits as a thank you gesture.
You can gift subs to viewers but at the moment you can't gift bits to fellow viewers. People who receive gifted bits can then use them to cheer their favourite streamers, or if they are already a streamer they can keep them for themselves. As an example sometimes there may have been someone generous who may have just gifted a load of subs to the community that in turn you may want to tip them some bits as a thank you gesture.