Simplify the following text for a Grade 6 native English-speaking person.
Original: On April 30 , 2009 , Twitter adjusted its web interface , adding a search bar and a sidebar of `` trending topics '' - the most common phrases appearing in messages .
Simplified: On April 30 , 2009 , Twitter changed the way it looks on the web . They added a search bar and a space on the right side of the page with `` Trending Topics '' .