OTG stands for “On The Go”. OTG cable enables your phone or tablet to act as a hosting device to other USB compatible devices and thereby makes the file transfers or controls possible.

It has a plug in which goes in to your hosting device (phone or tablet) and the other end would be a female port, to receive the usb compatible device. So, with the help of an OTG cable you can view/transfer files from your flash drive to your phone/tablet, work your usb mouse or keyboard, make connections possible with a variety of other usb devices.