Synthetic Transaction Monitoring (STM), also known as Synthetic Monitoring, is a web monitoring tool similar to Real User Monitoring (RUM), but Instead of collecting real user data, it simulates it. These scripts periodically visit websites and record the performance data from those sites for specific transactions and activities within the web application. STM is a form of monitoring that simulates actual user activity to collect specific data on application performance. It can be used to diagnose reported problems in your website or to proactively identify issues before you move your web application into production.
Both RUM and synthetic monitoring give you different views of your performance and are useful for a variety of things. RUM helps with understanding long-term trends, and synthetic monitoring helps diagnose and solve short-term performance problems. Each tool has its benefits and drawbacks, but when they work together, it’s extremely powerful.