Many English speakers confuse lecterns and podiums. A lectern is the piece of furniture that holds up a public speaker's notes, and the speaker stands behind it. At press conferences, an adjustable microphone is usually attached to the front of the lectern.  

A podium, in contrast, is the elevated platform that raises the speaker up for increased audience visibility. If you are a speaker, be careful as you mount the podium.  If you trip and fall, you will not make a good first impression on your audience.  (You may also injure yourself!)

You can remember the difference between the two in this way:

A LECTERN is the device that holds your lecture notes. People give lectures from behind a lectern.

The word PODIUM comes from podion, the Greek word for foot; you stand on the podium with your feet. (Your foot doctor is a podiatrist.)

A more formal word for podium is dais (pronounced DAY-iss).  You might use this word in a scabble game or to impress your friends with your big vocabulary!  (Other synonyms: platform, stage, podium, rostrum, stand.)