What is the difference between RNP and RNAV operations ?

Required navigation performance (RNP) is a type of performance-based navigation (PBN) that allows an aircraft to fly a specific path between two 3D-defined points in space. RNAV and RNP systems are fundamentally similar. The key difference between them is the requirement for on-board performance monitoring and alerting. A navigation specification that includes a requirement for on-board navigation performance monitoring and alerting is referred to as an RNP specification. One not having such a requirement is referred to as an RNAV specification. Therefore, if ATC Radar Monitoring is not provided, safe navigation in respect to terrain shall be self-monitored by the pilot and RNP shall be used instead of RNAV.

Area navigation (RNAV) is a method of instrument flight rules (IFR) navigation that allows an aircraft to choose any course within a network of navigation beacons, rather than navigate directly to and from the beacons. This can conserve flight distance, reduce congestion, and allow flights into airports without beacons. Area navigation used to be called "random navigation", hence the acronym RNAV

RNAV: Area navigation. Refers to any navigation that does not require the airplane to be heading directly to or from a radionavigation station. Example GPS, VOR/DME

Required navigation performance (RNP) is a type of performance-based navigation (PBN) that allows an aircraft to fly a specific path between two 3D-defined points in space. Area navigation (RNAV) and RNP systems are fundamentally similar. The key difference between them is the requirement for on-board performance monitoring and alerting

 (RNP) is a type of performance-based navigation (PBN) that allows an aircraft to fly a specific path between two 3D-defined points in space

Area navigation (RNAV) and RNP systems are fundamentally similar. ... One not having such a requirement is referred to as an RNAV specification.

RNP is talking about the tools or system required on on an aircraft  that allows an aircraft to fly a specific path.

RNAV is a navigation specification that includes a requirement for on-board navigation performance monitoring and alerting.

RNP is a statement of navigational position accuracy that has to be maintained in a designated airspace. 

RNAV is a method of navigation which involves flying directly point to point which Designated Operational Coverages of Ground-aids, without having the need to dog-leg all over the place wasting time and precious fuel.