Mindfulness is a state of focusing on what you're doing right now. Practicing mindfulness often leaves people feeling more relaxed and calm.
Since the 16th century, mindfulness has been used to mean "attention." Around 1995, it became popular to describe certain meditative practices using the Sanskrit sati, which translates to mindfulness. Beyond simply paying attention, this kind of awareness is focused on being fully present in the moment. If you've been feeling distracted and stressed out, you should try a mindfulness exercise!