newSubs used to subdomain enumeration by using [subfinder,assets-finder,findomain] tools and compare the output subdomains with old subdomains which you enumerate it before
chmod +x newsubs.sh
./newsubs.sh -d domain.com -o file-of-old-subdomains.txt
to use it every where type this command
sudo mv newsubs.sh /usr/local/bin/newsubs
chmod +x /usr/local/bin/newsubs
then you can use it at aney where on your system
this tool is important for pentester or bug hunter becouse many subdomains not be available every day or every week some of subdomains may open for some times and be closed again.