The fundamental distinction between a license and an easement lies in their legal nature and revocability. A license is a personal, revocable privilege to perform an act or series of acts on the land of another without possessing any estate or interest in the land. The property owner (licensor) can revoke this permission at any time. Conversely, an easement is a non-possessory interest in another's land, granting a right of use that is typically irrevocable, permanent, and "runs with the land," meaning it binds subsequent owners of the property.

B. An easement is a vested property right and cannot be unilaterally cancelled or revoked at will by the property owner who granted it.

C. A license does not require consideration to be valid; it can be granted gratuitously, such as when you invite a guest into your home.

D. While often part of a transaction, consideration is not a strict legal requirement for the creation of a valid easement, which can be granted as a gift.

1. Massachusetts Supreme Judicial Court Case Law: In the landmark case Baseball Pub. Co. v. Bruton, 302 Mass. 54, 55 (1938), the court explicitly distinguished the two, stating, "A license is merely a permission to do a particular act or series of acts on the land of another without possessing any estate or interest therein... It is not assignable, and is revocable at will by the licensor." This case establishes the revocable nature of a license as a core principle in Massachusetts law.

2. Academic Legal Treatise: The Restatement (Third) of Property (Servitudes), a highly influential academic publication, defines a license as "an oral or written permission given by the occupant of land allowing the licensee to do some act that otherwise would be a trespass." It further clarifies that a license is revocable, distinguishing it from easements, which are property interests. (See § 1.2 and § 2.2, American Law Institute).

3. University Courseware (Property Law): Standard property law curricula in reputable law schools teach that a key feature of a license is its revocability at the will of the licensor, which contrasts with the more durable property interest of an easement. This principle is foundational to the study of non-possessory interests in land. (e.g., Dukeminier, J., et al., Property, 9th ed., Aspen Casebook Series - A standard text used in numerous university law programs).