TheHarvester is used to gather emails, subdomains, hosts, employee names and etc. The tool is only available in CLI but is very straightforward.
For demonstration purposes, we will try to gather information on microsoft.com via google search engine using the first 100 entries.
To start the program, use theharvester -d microsoft.com -l 100 -b google. The program will quickly scan and show all results found such as emails, IPs and etc. .