^
Bash builtin to quick substitute a string in the previous command and run the result.
TLDR
Run the previous command replacing string1 with string2
$ ^[string1]^[string2]
Remove string1 from the previous command
$ ^[string1]^
Replace string1 with string2 in the previous command and add string3 to its end
$ ^[string1]^[string2]^[string3]
