By "Indexing Files", what you really mean is Windows has a giant database that tells the operating system where each file location is in the file system. This giant database is organized and updated by the Windows Search service.
"Indexing" means the database is organized by a certain field so that the way you try to find something on a computer is faster.
https://en.wikipedia.org/wiki/Database_index
Not sure why an SSD would be harmed by this, considering it is simply a file, and TRIM would keep used/unused SSD cells from immature deterioration.