| syp | SYP Script |
| sysml | Systems Modeling Language Document |
| syt | Sytes Template File |
| t | Turing Source Code |
| t | Tom Source Code |
| t6i | Mazak 640-MT Mazatrol Program |
| t6m | Matrix Mazatrol Program |
| taguit | thinBasic Debugger Data |
| targets | MSBuild Targets File |
| tb1 | Borland Turbo C Font Data |
| tbasic | thinBasic Script |
| tbasicc | thinBasic Console Script |
| tbasiccx | thinBasic Encrypted Console Script |
| tbasicx | thinBasic Encrypted Script |
| tbk | Visual FoxPro Memo Backup |
| tch | Turbo C Help |
| tcl | TCL Script |
| tco | MSX C Temporary Code |
| tcs | Tahoe Server Content Source |
| tcsh | TCSH Shell Script |
| tcv | SD Test Coverage Vector File |
| tcz | TDF Czar Script |
| tdb | ProWorx NXT Title Data with Blocking |
| tdbd | TurboDB Database |
| tdf | ProWorx NXT Title Data File |
| tdk | Borland Turbo Debugger Keystroke Recording Data |
| tdl | MathType Translator Definition Language |
| tdm | LabVIEW Binary Measurement with XML Header |
| tdms | LabVIEW TDM Streaming Data |
| tds | Turbo Debugger Symbols |
| tdw | Turbo Debugger for Windows Data |
| tdx | LabVIEW Binary Measurement Data |
| tem | Microsoft Frontpage Website Template |
| tes | Tool Encapsulation Specification |
| tf | Xilinx ISE Verilog Test Bench |
