Jettro Coenradie's article explores the use of Elasticsearch's percolator feature in combination with geo points to build a basic classification system for geographic data, exemplified through a sample application involving Dutch zip codes and provinces. Elasticsearch's geo support is highlighted, including its ability to store and manipulate geolocations with features like geo shapes and geo polygon filters, which are essential for identifying and categorizing locations within specified areas. The sample application, built with Spring Boot and AngularJS, demonstrates the data lifecycle stages, from obtaining and transforming data to storing and utilizing it for geographic queries. The percolator feature is particularly emphasized for its role in inverse querying, where queries are stored and documents are matched to them, allowing the application to determine the province of a city based on its coordinates. The article concludes by suggesting potential enhancements, such as tracking user interactions with the application to improve data accuracy and user experience.