how to find which shell I am using currently

I wanted to know if I can find the shell which I am using currently,
below is the method I tried out

$
$bash
bash-2.05$
bash-2.05$ echo $SHELL
/usr/bin/sh

bash-2.05$finger -m username

Login name: username In real life: Full Name
Directory: /home/username Shell: /bin/csh
On since Oct 25 16:28:23 on pts/2 from user.domain.com
3 minutes 52 seconds Idle Time

you can see that I changed my shell to bash but both the commands show
different shell environments?

What if I need to find which shell I am into now?
Thanks,

.