Definition of niggling for English Language Learners. : causing you to feel a slight pain or to be worried or annoyed for a long time.
What is PPAP? The Production Part Approval Process (PPAP) is a standardized process in the automotive and aerospace industries that helps manufacturers and suppliers communicate and approve production designs and processes before, during, and after manufacture.
PPTP (Point-to-Point Tunneling Protocol) is a network protocol used in the implementation of Virtual Private Networks (VPN) .PTP works on a client server model. PPTP VPN clients are included by default in Microsoft Windows and also available for both Linux and Mac OS X. Newer VPN technologies like OpenVPN, L2TP and IPsec may offer better network security support, but PPTP remains a popular network protocol especially on Windows computers.