Hackers and security experts use various custom and open source tools tocomplete their tasks.
In fact, one of the tools they use you probably useevery time you browse the web, the Google Search Engine.I remember the first time I used the Google Search Engine years ago. I was amazed at how quickly it fulfilled my search request.
Google's huge indexof systems / information and it's ability to perform complex searches haveevolved over the years. When we performed security assessments andpenetration test, we regularly use Google to locate information thatorganizations typically want to keep private and confidential.