If this is your first time hearing the term OSINT that is perfect because I can briefly explain it below for you to understand.
What is OSINT?
Open Source Intelligence(OSINT) is the practice of collecting information from published or public data sources. For example, if you want to use either of the tools below, you can grab ample information on websites, files, and many more. If you are working on an investigation, these tools can help direct you to decide on a particular outcome.
Why should you use OSINT?
For one, most of the tools are free. This is a major plus since you can use these tools at any time, and it can help you in your day-to-day.
Top 10 OSINT tools that I use on a daily as a Security Professional
VIRUSTOTAL
URLSCAN.IO
ABUSEIPDB
APP.ANY
Netcraft
Shodan
Spyse
Searchcode
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