The Uno with socket is a development board with an ATmega328P chip that can work with a whole line Atmega48/88/168/328 to custom fit an end-product. The goal is to pry the chip out and put it in a socket on proto-board or a PCB of your own. This is a goal set by Arduino on the main site you can reach by clicking ARDUINO.CC in the upper left corner of your forum window.
But AVR chips are so self-contained, the possibilities include no board at all.
On the main site see the DOCUMENTATION drop-down menu. Bookmark everything that looks like you'll need it someday,
This is the Hacking homepage with much you want now.
Hey ALL! Arduino has done some re-arranging. Foundations is now in Arduino DOCS.
This may be one of your main look-up resources, Arduino Foundations -- updated.
Be sure to check out The Playground. There is a whole manual in the main site pages, it is not thin.
Learn non-blocking code, we could use more helpers here!