Tiger Files are typically organized by county. Each county consists of a set of about 16 files all having the same file name with different extensions.

Every few years the Census Bureau comes out with a new set of Tiger files for the country and occasionally the format changes. Think GIS is currently designed to work with Tiger 1999 and Tiger 2000 files. To download Tiger files go to

https://www.census.gov/programs-surveys/geography/guidance/tiger-data-products-guide.html