Activity recognition is a research area that focuses on the development of algorithms and systems capable of automatically identifying the actions or activities being performed by individuals based on sensor data, such as data from accelerometers, gyroscopes, and other sensors embedded in devices like smartphones or wearable devices. This research area has applications in various fields, including healthcare, sports monitoring, security, and human-computer interaction. By accurately recognizing activities, these systems can provide valuable insights for monitoring health and fitness, detecting falls or accidents, improving sports performance, enhancing security measures, and creating more intuitive user interfaces for technology use.