is there a Multi-threading function in Arduino

I'm c#.net and vb.net programmer , and there is a library called Multi-threading to run 2 processes together , i want to know if there is something similar in Arduino Language

I'm c#.net and vb.net

You'll get over it, given time.

Have a look at the blink without delay example in the IDE.

There are background timing based sequencer libraries to do things at a certain time, and schedulars, and rtos libraries.
There are also pre-emptive multitasking libraries for the Arduino. I know that many libraries are not written for something like that, so it might cause a lot of troubles.

Google for : arduino rtos
It would be nice of one of them was officially supported.

The thread in the following link includes a demo sketch that I wrote to show how the concepts of Blink Without Delay can be used to control several things at the same time.

http://forum.arduino.cc/index.php?topic=223286.0

...R