Clarification of the difference between London Bridge and The Tower Bridge

If you do a picture search on Google and write London Bridge,
around 80-90% of the pictures will show you The Tower Bridge and not the London Bridge.

Here is a picture of The Tower Bridge:

And this is a picture of London Bridge:
(Source: both bridge photos are Google images)

ok, i will have to add a Youtube clip of the famous song "London Bridge is falling Down" in case there is someone that have not heard it.. ;)

(Source: Youtube video)