Who is Martin in The Old Man and the Sea I have to answer Describe the function of Martin proprietor of the Terrace in the novel in 3 paragraphs and I don't know who he is?

Martin is the man who works at the terrace. I believe he is mentioned in the very beginning and very end of the book. He gives the old man Santiago free coffee and comforts the eighteen-year-old boy when Santiago's skeleton of a fish arrives on their beach.