Do I even have to say anything? I can't remember one name who doesn't know who Sherlock Holmes is and how famous he is. It is one of the classics and very well deserves to be so. I don't think you'll need a lengthy description on this book. It is just marvelous, I just wish I was a keen observer and deducer like Sherlock. 
 Do you know one thing? When it was first released people thought that Sherlock was real and went to meet him in 221B, Baker Street, hoping to make Sherlock solve their cases. The people of Baker Street were tired of shooing strangers from peeking through their windows, probably trying to find the detective Sherlock Holmes! So you obviously get that picture how realistic the book is and how famous it is still now after so many decades.