Processes do not have names. That's the first thing that's confusing you. For some reason you think they do.

"steve" is your user name. It is certainly not a process name.

When you run a command like "ps -ef", the string "ps -ef" is a command line. Your shell will locate a file called "ps" ( probably in /usr/bin/ps) and it will run it. Some people will often say that "ps" is the process' name in a case like this.

Each process gets a unique number called a pid. This number might have a stronger claim to being a process' name.

The instances of csh that show are an interesting case. Notice the "-csh (csh)". When the login program invoked /usr/bin/csh it passes arguments to it. Normally, argument 0 is the name of the file that is running. But if you write in c, you can set that argument to anything. The login program puts a minus sign in front of the file name. csh inspects the first argument and if it starts with a minus sign, it acts like a login shell.

Some people will call argument 0 the process' name. Others go with the name of the file that is running. Your ps program noticed that they different, so it showed both.

So a process had a pid, which is unique to it. It has a file name that it came from which is not necessarily unique. And it has a argument 0, which is often the same as the filename. Take your pick which, if any, you want to call a process name.

In my mind, ps, csh, etc are the names of programs. You and I can both run the ps program at the same time. If we do we get different processes. And our processes have only a number, not a name.

If you are running csh as your shell, you could type the command "exec sh". csh would then overlay itself with sh and you would be running a new shell. But the process would be the same. Try it:
ps -f
exec sh
ps -f
You get a new shell, but you're still using the same process.