What is the difference between SBC & Development board?
Most of the difference is Marketing.

Development boards are educational products designed to highlight the strengths of the core IC or Microcontroller they are designed around. They are rarely cheap (though the last three years has brought a lot of loss leader dev kits), and often have a lot of single purpose parts, just to show how flexible the core ICs are. They are rarely intended to be bought in bulk to be included in OEM designs. Basically "hey look at our amazing Product X, see how much stuff it can do, you should buy a bunch of it".

SBCs are full featured boards designed to be used individually or as part of a bigger product (as embedded computers). It is a product by itself. 

There is much overlap between the features offered in the two. If you are going with a one off project, the only thing you need to worry about is proper documentation and ease of use, aside from if it has what you need. A dev kit or a sbc would both fill your needs.

Though I do have to say, the ""sbc"" you linked to is a VERY VERY poor and uncharacteristic example of a sbc. Almost NOTHING is included. It's really a breakout accessory board at best. And at that price... A Raspberry Pi is a 25 dollar full featured computer. A beagle Bone Black is 45 dollars and beats even that, and they both could beat top of the line 2003 computers, computers that would cost 1000+ dollars brand new.