| spx | ArcGIS Geodatabase SPX File |
| ssf | Trimble SSF Data |
| stn | ArcView Geocoding Standardization |
| strk | GeoLogger GPS Track Data |
| style | ArcGIS Style File |
| sup | SOCET SET Support File |
| svy | AGPS-Shape Pro Data Point |
| sxd | ArcScene Document |
| sxf | GIS Storage and eXchange Format File |
| sxw | SuperMap Desktop GIS XML Workspace |
| sxwu | SuperMap Desktop GIS 6R XML Workspace |
| tab | MapInfo Table Document |
| tat | ArcView Text Attribute Table |
| ter | Map Maker Terrain File |
| tfw | ArcGIS TIFF World File |
| tifw | ArcGIS TIFF World File |
| timestamp | ArcGIS Geodatabase Timestamp File |
| tlw | TripLogik TL1000 RAW Data |
| tpk | ArcGIS Tile Data Package |
| tpo | Topo Explorer Map |
| tqm | Traqmate Data File |
| trip | Garmin Nuvi Trip Data |
| tro | Visual Topo Document |
| tsd | TNTmips TileSet Definition Data |
| ttbin | TomTom Adventurer Route Data |
| ttkgp | TatukGIS Project |
| ttmd | Trail Tracker GPS Map Data |
| twl | Naviguide Binary GPS Track Data |
| twz | TerraGo Collaboration Package |
| tzd | TimeZero Exchange Data |
