"The Registered Behavior TechnicianTM (RBT®) is a paraprofessional who practices under the close, ongoing supervision of a BCBA, BCaBA, or FL-CBA. The RBT is primarily responsible for the direct implementation of behavior-analytic services. The RBT does not design intervention or assessment plans." (https://bacb.com/rbt/)
The RBT Task list is a document that describes various concepts that a Registered Behavior Technician must be familiar with in order to perform their services in a quality and effective manner.
There are many topics on the RBT task list including: Measurement, Assessment, Skill Acquisition, Behavior Reduction, Documentation and Reporting, and Professional Conduct and Scope of Practice. (https://bacb.com/wp-content/uploads/2016/10/161019-RBT-task-list-english.pdf)