The Distinct feature in Algolia enables developers to deduplicate records on-the-fly based on a specific attribute, improving the relevance of search results. This feature is particularly useful for handling large documents like PDFs or web pages by splitting them into multiple records, reducing false positives and noise. By introducing an attribute with a unique value for each record and setting `attributeForDistinct` in the index settings, Algolia can remove duplicates and keep only the best match for each query. This feature also allows for faceting, grouping, and displaying search results without duplicates, making it easier to build interfaces like AngelList. However, faceting with distinct enabled can become a headache due to the computation cost, and Algolia has implemented both approaches that can be computed in real-time, using `facetingAfterDistinct=true` as the standard behavior. The Distinct feature has been introduced in December 2013 and improved significantly in July 2015, allowing for better indexing of big records and giving birth to the DocSearch project.