Windows 10 has been updating the search to only use Cortana, Microsoft’s digital assistant. This assistant might be useful to you and Microsoft has put a lot of time in making Cortana reasonable to use.
Some people would rather have the good old basic search that only shows the programs and the files on your local computer without all the web results and options fro the assistant. Recent updates from Microsoft have change the location of the settings so that you must sign in to Cortana in order to disable options like ‘Show Web Results‘.

There is a way to disable Cortana and change her back to a dumb search box for your system with a few simple edits to the windows registry. Be warned that changing the registry can have major impact on your systems stability if you are not careful.