The TI-Nspire product line is a series of graphing calculators developed by Texas Instruments. This line currently includes the TI-Nspire, TI-Nspire CAS, TI-Nspire CX and TI-Nspire CX CAS. There are models aimed for Chinese market, named as TI-Nspire CM-C, TI-Nspire CX-C, TI-Nspire CM-C CAS, TI-Nspire CX-C CAS. There is also software available for Windows and Mac OS X that act in similar ways to the calculators and allow the user to create compatible files. This software either requires a license or can only be used for a limited time. However, Texas Instruments also provides separate software that can be used for an unlimited time without a license but only allows file transfers and not emulation of the calculator. In 2010, Texas Instruments updated the calculators to the Touchpad versions which come with the Nspire or Nspire CAS computer software and support optional rechargeable batteries. In 2011, TI announced two new models of the TI-Nspire series: Nspire CX and Nspire CX CAS. The main new features are the color screen, rechargeable battery and thinner design.