Conversion from One Format to Other

//Conversion from One Format to Other
>>a=imread('monarch.png');
>>b=rgb2gray(a);
>>c=im2bw(b);
>>subplot(1,3,1), imshow(a), title('Original Image');
>>subplot(1,3,2), imshow(b), title('Gray Scale');
>>subplot(1,3,3), imshow(b), title('Binary Image');