Ophcracker is a free windows password breaking program. It uses rainbow tables to find which hashes have which passwords. But I’m getting ahead of myself by now.
Windows does not store passwords as plain text files, because programs could read them and the password would be moot. Instead, Windows stores passwords as hashes, which are derived from the password but there is no way to tell from the hash what the password is- unless you use rainbow tables. That’s it for today, tune in tomorrow!