Simplify the following text for a Grade 8 native English-speaking person.
Original: Brenda Mae Tarpley ( born December 11 , 1944 ) , better known as Brenda Lee , is an American performer who sang rockabilly , pop and country music , and had 37 US chart hits during the 1960s , a number surpassed only by Elvis Presley , The Beatles , Ray Charles and Connie Francis .
Simplified: Brenda Mae Tarpley or Brenda Lee ( born December 11 , 1944 in Atlanta , Georgia ) was an American pop singer popular in the 1960s .