What appid I should use for Counter-Strike Source Dedicated Server?

[Daren]

Hello.

Please, can somebody explain me what difference is between:
Source SDK Base 2013 Dedicated Server (appid 244310) (have Steam client)
and
Counter-Strike: Source Dedicated Server (appid 232330) (no Steam client)

And if I want to edit a menu or a behavior in cs mods / plugins or create my own plugin, do I need an SDK or not?

valve wiki

Quote:The Source Dedicated Server or SRCDS is a tool that runs the server component of a Source game without the client component.

And what does the "Steam client" do in app 244310?