Microsoft has announced that, starting January 12, 2016, it will only be supporting the most recent version of their Internet Explorer web browser. This means that Internet Explorer 11, its latest, will be the lone version receiving security updates, technical support, compatibility fixes, and more on Windows 7, Windows 8.1, and Windows 10. Microsoft has advised those using the older versions to upgrade to 11 for a faster and more secure browsing experience.
How does this affect me?
-Security updates patch vulnerabilities that may be susceptible to malware attacks, keeping data safer for users. Going forward these will only be available for IE 11
-Enterprise Line of Business systems may need to use "Enterprise Mode" to run legacy web applications that don't support IE 11, however the best practice recommendation is to upgrade the applications to run on the latest browser.
-Upgrade assistance, planning, customizing and deploying Internet Explorer 11 is available here
-It's a great time to consider upgrading your legacy applications to SharePoint Online!
How does this affect SharePoint?
-In the future, Microsoft may release features in SharePoint or SharePoint Online that will not work in unsupported browsers.
-In the past designers have had to forego modern design techniques in an effort to support a large number of browser versions. The long term benefit here is that there is dramatically improved support for modern design techniques like CSS 3 and HTML 5. For those that say "I don't want it to look like SharePoint", you can deploy your design with confidence that your users will have a more consistent experience.
You can read more about the details on the end of support for older versions of IE from the Microsoft team here.