JS Link is a new web part property in many SharePoint 2013 web parts. It allows users and developers to create Client-Side Rendering (CSR) solutions within SharePoint 2013. In other words, it allows alternate formatting, data and functionality to be manipulated within a web part.
Covers several approaches for user interface customization in SP2013 – using JSLink to customize a list and/or view, creating custom Display Templates for the Content Search web part, and different approaches for customizing the search hover panel.
The client’s use case was as follows: they needed a way to be able to plot office locations on a map with contractually agreed to boundaries around them. These boundaries may be a specific radius around an office location or an irregularly shaped polygon. Once these are plotted on the map they required the ability to plot an address on the map to determine whether the address fell within any of the predefined boundaries.
A simple example of how you can utilize the REST Search API’s in SharePoint 2013 to perform a search.