Energy is omnipresent in everything and makes up everything. It can come in many different forms, there are different types and there are two orientations for every energy type and form.
Elemental Energy was the most common and known energy type and came in different forms that were well known by cultivators and used by those that had elemental affinities, but there are also other types of energy.
Attributeless energy, although plain and didn't have any special characteristics, was pure energy and could still be used to unleash powerful attacks. It was also known as positive energy when was wielded with positive intentions or cultivated through reasonable means.