Ugh don't understand this!

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class FunFactsActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fun_facts);

        // Declare our View variables and assign them the Views from the layout file
        TextView factLabel = (TextView) findViewById(R.id.factTextView);
        Button showFactButton = (Button) findButtonById(R.id.showFactButton);
    }
}