The paper describes Trigger and Data Acquisition (TRIDAQ) systems of accelerator experiments for High Energy Physics. The background for physics research comprises assumptions of the Standard Model theory with basic extensions. On this basis, a structure of particle detector system is described, with emphasis on the following functional blocks: Front-End Electronics, Trigger and DAQ systems. The described solutions are used in the LHC experiments: ATLAS, ALICE, CMS and LHCb. They are also used in other accelerator experiments. Data storage and processing functionality is divided into two hardware systems: Trigger and Data Acquisition, that are dependent on each other. High input data rate impose relevant choices for the architecture and parameters of both systems. The key parameters include detailed system structure and its overall latency. Trigger structure is defined by the physics requirements and the storage capability of DAQ system. Both systems are designed to achieve the highest possible space and time resolution for particle detection. Trigger references are reviewed [1]-[39] as well as chosen accelerator research efforts originating in this country [40]-[83]
