The Task format is MOSEK’s native binary format. It contains a complete image of a MOSEK task, i.e.

The format is based on the TAR (USTar) file format. This means that the individual pieces of data in a .task file can be examined by unpacking it as a TAR file. Please note that the inverse may not work: Creating a file using TAR will most probably not create a valid MOSEK Task file since the order of the entries is important.