Why do we need selenuim RC if there is Selenuim IDE?

Can anyone please explain me why do we need selenuim RC if there is Selenuim IDE.

Selenium IDE is a record and play tool where you couldn’t do below things without installing plugins:

Framework development Looping Screenshot extension Nice GUI Reporting

There are many more. These are just which comes to my mind as of now.

Also, I would suggest you to switch to Selenium Web driver instead of selenium rc because no company is using it now.