Self-Monitoring, Analysis and Reporting Technology (S.M.A.R.T., often written as SMART) is a monitoring system included in computer hard disk drives (HDDs) and solid-state drives (SSDs). Its primary function is to detect and report various indicators of drive reliability with the intent of anticipating imminent hardware failures. When S.M.A.R.T. data indicates a possible imminent drive failure, software running on the host system may notify the user so preventive action can be taken to prevent data loss, and the failing drive can be replaced and data integrity maintained.