Internet Explorer/What is it?

Microsoft Edge(formerly called Project Spartan) is a browser that is touted to be the successor of Internet Explorer. It should be noted that their are significantly major differences in hand between the two browsers which you must be aware of.

1. It is available only on Windows 10.
2. It uses a different rendering engine , some websites working on Internet Explorer can break on Project Spartan. This is done to alleviate the problems on Internet Explorer's Trident Engine , as many websites detect Internet Explorer and apply ugly 'fixes' meant for older versions of Internet Explorer(mostly before version 7).
3. It features a much streamlined interface compared to Internet Explorer.
4. It features deep integration with Windows 10's Cortana , allowing you to 'speak' to the browser.
5. It allows updates to be delivered through the Windows Store instead of a major system update , this allows faster updates.
6. It has better use for touch , you can draw on the webpage. It also features better integration with OneNote.
7. Addons will be removed or changed.

However , most of the features present on Internet Explorer 11 will carry over to Project Spartan , and this includes important features such as the Internet Explorer/F12 Developer Tools , Download Manager and safety protections

This means that you do not have to mostly bother which one of the two you are using , both will do what you want. Also , Internet Explorer is not going anywhere , it is officially stated that Windows 10 will carry both browsers , with Internet Explorer handling the functions for older websites and businesses which need it.