You need to upgrade your legacy campaigns to enhanced campaigns by July 22nd.
Enhanced campaigns are essentially Google pushing advertisers toward multi-device and location targeting via one campaign. With it comes all sorts of useful new ad extensions and tools.
Please see Google's official line on it here:
If you go to the main left menu within your AdWords interface and click on 'upgrade center' Google gives you a step by step guide to upgrading. Just click "get started".
You should do this before Google forces you in July.
Does this help?
In addition to what Jack said above, I would like to add that Enhanced campaigns by default will run on all devices i.e. desktops, laptops, tablets, mobiles etc...
So you need to be well prepared while doing the upgrade because there are many new features added to ECs which aren't there in Legacy campaigns.
Also, one important note that the process of upgrading to ECs is not reversible i.e. you cannot go back to Legacy settings once you are done with the upgrade. I would also encourage you to read this PDF guide before you upgrade to ECs.
My 2 cents!