grep -i in UNIX

You can force grep to ignore word case with -i option.
In our file 1.txt , we have the content "I am from forget code"

grep in general purpose:
grep 'CODE' /var/root/*

Output:
No output

grep in ignore case:
grep -i 'CODE' /var/root/*

Output:
/var/root/1.txt:I am coming from forget code