Excel File in Arduino

Guyz i just started arduino controller and it has great fun. now i want to log my data in arduino controller and when i insert pendrive in it i will get data in pendrive in .xls format it is possible?

Where are you expecting to insert the pendrive on the arduino? Instead of trying to save the data in Microsoft's proprietary .xls format you could save it as .csv that Excel can import/open.

You could do it using a a USB host shield, but I think most people use an SD card. It's probably a lot cheaper. The file would be a simple CSV file as suggested.