System Design: The Typeahead Suggestion System

Introduction

Typeahead suggestion, also referred to as the autocomplete system, is a front-end functionality that provides real-time search query suggestions as users type. It enables users to search for a known and frequently searched query. This feature comes into play when a user types a query in the search box. The typeahead system provides a list of top suggestions to complete a query based on the user’s search history, the current context of the search, and trending content across different users and regions. Frequently searched queries always appear at the top of the suggestion list. The typeahead system doesn’t search faster. However, it helps the user form a sentence more quickly. The underlying algorithm determines the relevance and ranking of suggested terms.