Why is that carbon can form an infinite number of molecules?

Question

http://web.jjay.cuny.edu/~acarpi/NSC/10-organic.htm

http://www.scienceclarified.com/everyday/Real-Life-Chemistry-Vol-2/Carbon.html

http://biology.clc.uc.edu/courses/bio104/carbon.htm

Answer 1

carbon chemistry

Answer 2

everything about carbon chemistry