Influenced by Dinah Washington, Nat “King” Cole and other stars, Wilson covered everything from jazz standards to “Little Green Apples” and in the 1960s alone released eight albums that reached the top 20 on Billboard’s pop charts. Sometimes elegant and understated, or quick and conversational and a little naughty, she was best known for such songs as her breakthrough “Guess Who I Saw Today” and the 1964 hit ”(You Don’t Know) How Glad I Am,” which drew upon Broadway, pop and jazz.