Is cydia the same as the app store?

Just wondering how cydia works for the iphone? Is it just the same as app store only with more apps or does it store apps on cydia?

Yes it is.

It gives you the opportunity to download applications which use everything on your iDevice.

The standard iDevice is VERY limited. Cydia uses everything it can do and gives you very fun and usefull apps.

All code in the appstore is very secure as its reviewed before it gets there, so you can download as much as you want without virus concerns.

In a way. Not apps per sé, but tweaks.