Recommender systems are essential today due to the vast amount of content and information every product provides. It’s unfair and unrealistic to expect users to consume and filter this wealth of information as needed; hence, the need for recommender engines arose.

Almost every platform—from Amazon, Netflix, and YouTube to Facebook, Spotify, and even Medium have their own recommender systems to personalize, filter, and present information and content users are likely to enjoy.

Recommender systems are a secret weapon that many products and services invests a lot in in order to deliver relevant content that matters to the user, thereby boosting user engagement and traffic. It’s essential for e-commerce products to get this right. A good recommendation system can boost their sales which eventually leads to better profits.

Types of Recommendation Systems

Typically, recommender systems are built using the following paradigms:

The content-based method relies on item similarity, based on the various common attributes that the users/items have. For example, for a movie recommendation, tags such as genre, director, and year of release are some of the key attributes that play a role in recommending movies to the user.

On the other hand, collaborative filtering recommends items to a user based on other users' preferences. Based on the kinds of items the user likes, it recommends new items that users with similar preferences had liked in the past.

Both categories have their own sets of pros and cons. While content-based recommendations rely on the user and item information (and thereby threaten to invade a user’s privacy to an extent), collaborative filtering depends only on user-item interactions. Collaborative filtering requires a substantial amount of historical data for building accurate recommendation engines.

Bringing recommendation systems onto mobile devices is a big step in user privacy. It gives the user more confidence over the content it’s interacting with by ensuring that their information stays on the device. Plus, anything that works data-free is a big bonus.