Descriptions are given for the 164 computerized files that comprise the Texas Natural Resources Information System (TNRIS). The system provides natural resources information to federal, state, regional, and local and private entities. File descriptions are organized under the following data and information content areas: (1) base data, (2) meteorological resources, (3) biological resources, (4) water resources, (5) geologic and land resources, and (6) socio-economic resources. Each file description includes the file name, unique file number, narrative description of file contents, state agency responsible for collecting file data, geographic coverage, frequency of update, units of measurement, and data retrieval publications (i.e., procedures manual). A summary table listing special characteristics, availability of reports, and data processing method for each file is appended. (JPF)