what is ^ in bash?

Regular expressions are not very friendly for many linux administrators. I will try explain this regular expression ^. 

In English keyboard ^ you find with SHIFT+6! 

How it works? 

We have some file and we need find dhcp servers. 

Is it easy? Let me try! 

cat file | grep -i dhcp 

output

dhcp=18.21.51.98

#If you want DHCP servers please burn......

while dhcp ....

starting dhcp....

ok.... everything is fine but dhcp is not on the begining of line. 

Please try with ^!

cat file | "^dhcp*"

output: 

dhcp=18.21.51.98

that's all!

remember: 

1) regular expressions need ""

2) ^ is begining of line