An easement is a legal right to use property that actually belongs to someone else. Most easements are non-exclusive by nature, as the underlying property belongs to someone other than the individual, or individuals, who are granted the easement. Non-exclusive easements exist in residential areas, including subdivisions.
Easements can be created in a variety of ways. Often, easements are granted in property deeds; these are called easements by "express grant." Sometimes easements are created by implication, meaning the easement is granted because it's implied by prior use. Easements can also arise out of necessity. For example, if a parcel of land would be otherwise landlocked, the owner of the landlocked property can get a court to grant him an easement so he can access his property.
Ingress and Egress
The majority of easements allow for ingress and egress. Ingress in the ability to enter, and egress is the ability to exit. Some easements are given to utility companies for sewer and power lines. These types of easements also include the right of entry and exit; however, whether the easement is exclusive to one particular utility company depends on the wording of the instrument that granted the easement.
Most easements are non-exclusive. For example, many easements are driveways that allow homeowner's to cross over the land of another homeowner. These types of easements are non-exclusive, as the owner of the underlying land cannot be excluded from using his own property. In rare cases, courts have declared residential easements exclusive to one party. However, courts usually only declare an easement exclusive if one party has improved it to such an extent that removing the improvements would cause hardship to the party that built the improvements.
Sometimes courts will declare an easement exclusive if not doing so would lead to disputes between neighboring property owners. Additionally, courts have declared easements exclusive where one party was mistaken as to the true boundary line and made substantial improvements.