public class AudioRecorder : IAudioRecorder
It declares/defines a class named
AudioRecorder
that implements the interface named
IAudioRecorder
.
class AudioRecorder {}
public class AudioRecorder{}
The former defaults to an
internal
class, the latter explicitly declares it as a
public
class.
BTW what you are asking is pretty basic C# stuff, so perhaps you need to start with an introductory book on the subject before you venture out into actually using the language.