Advantages of Skype web
You can use and only need an internet connection and access to a web browser, so you do not need to download any application, either by restrictions on the computer or because you do not have enough space or permissions to make modifications to the computer. With Skype online web you can chat online and do not need to download anything.
I do not have Skype account how do I sign in?
The implementation of facebook at the time of logging in allows you to enter your Messenger online without having to create a new account, you just have to log in to facebook and you're already using Skype.