X

 X  is the 2 5 t h letter  of the English  alphabet. Use d in various  SESAME STREET  sketch e s as a prop or concept, the Letter X has also appeared as a Muppet   character  on multiple occasion s , such as be in g  serenade d  by  Patti La Belle  or as a mystery guest on  Mystery Guest.

The letter  first sponsored  Episode 000 6.

Song s about X

 * " X Mar k s the S pot !  "
 * " Oh, H ow I Miss My X  "

Sketch e s about X

 * The Type write r - X - X - ray
 * Human letter s at the Beach