A/B Test

A/B testing is a method of comparing two versions of a webpage or app against each other to determine which one performs better. Often, an A/B test will give 50% of users experience “A” and the other 50% experience “B.” Product managers often help choose which variant is better (“A” or “B”) based on metric analysis.

API

Stands for Application Programming Interface. A product's API extends the functionality of the product to other parties. For instance, a Facebook API might allow other products (like Venmo) use Facebook log-in to authenticate users.

Beta Test

A trial phase of the product's launch. This is usually scoped to a select group of early adopter users, and the product may still have bugs in it.

Bounce Rate

The percentage of visitors to a particular website who navigate away from the site after viewing only one page.

Conversion Rate

The percentage of visitors to a particular website who complete a desired goal (e.g. pay for a service)

Churn Rate

The percentage rate at which customers unsubscribe or don't retain as users of a feature or product.

CTR