Arcane Weave

The Arcane Weave is the term to describe the metaphysical fabric running through everything, the manipulation of which allows for magical effects. It is intrinsically tied to the governing laws of physics and allows those with the proper ability to manipulate, bend, and even completely overturn the laws that normally govern space and time.

Put in more modern terms, it is the base computer code that governs our reality. Powerful, but also open to manipulation with the right techniques.

From DMG:

The Weave is an essential element of the universe, running through everything in unseen threads. Some creatures, objects, and locations have deep, intrinsic ties to the Weave and can perform extraordinary feats that come naturally to them (a beholder’s flight, a vampire’s charming gaze, a dragon’s breath weapon, and so forth). Creatures with the necessary talent and skill can also manipulate the Weave to perform magic by casting spells.
The Weave isn’t normally visible or detectable, even through the use of spells. Detect magic doesn’t let you perceive the Weave, for instance. The Weave isn’t magic, precisely, any more than a collection of threads is a garment; it’s the raw material from which the tapestry of magic is woven.

Type

Metaphysical, Arcane