Question

what is Skype? mention any two basic requirements to use this software.

Answer 1

Skype is an IP telephony service provider that offers free calling between subscribers and low-cost calling to people who don't use the service.
System Requirements
Skype runs on computers with Windows, Mac, and Linux operating systems, Android and iOS mobile devices, and web browsers. Using the latest version of Skype, specific requirements are:

Windows Desktop and Laptop Computers

Windows 10, 8.1, 8, 7 with IE 11, Vista, or XP SP3 with IE 8 or higher (New Skype for Windows requires Windows 10, 8.1, 8, or 7)

Answer 2

Skype is a computer program that offers a VoIP ('Voice over Internet Protocol') service.
 
1. a Skype account and the Skype program installed on your computer.

2. speakers and a microphone – many computers have these built in (especially laptops), many webcams also come with a microphone and you can also use a headphones-and-microphone headset that can be bought quite cheaply.