What is a plist?

A property list, often known as a list, is a list that uses various object types to arrange data into named values and lists of values. These kinds give us the tools we need to create data that is well-structured, transportable, storable, and accessible while being as efficient as feasible. Property lists are widely used by both Mac OS X and iOS apps. We can convert hierarchically organized combinations of these fundamental sorts of objects to and from standard XML using the property-list programming interfaces for Cocoa and Core Foundation. The XML data can be saved on a disc and used to rebuild the original objects later.
Property lists are used to hold objects representing user preferences in the user defaults system, which we can access programmatically using the NSUserDefaults class. Many types of items, such as NSColor and NSFont objects, appear to be excluded from the user defaults system due to this restriction. Objects that comply with the NSCoding protocol, on the other hand, can be archived to NSData objects, which are property-list compatible.