The Index keeps track of the files on your computer and stores information about the files, including the file name, date modified, and properties like author, tags, and rating. The index is used to make searching for files in Windows much faster. Instead of looking through your entire hard disk for a file name or file property, Windows scans the index, which allows most results to appear in a small fraction of the time that a search without the index would take.
The index will often run (indexing) in the background to rebuild and update for changes made to the included index locations
since the last index rebuild to increase search result accuracy. This will show you how to pause indexing
for 15 minutes at a time
if you happen to need the extra resources at that time. After 15 minutes indexing will resume.