Is there a difference if vectors are lined up horizontally or not?

[gtfitzpatrick]

Just a quick question
is there a difference if the vectors are lined up horizonatally or vertically?
eg:
(a)
(b)
(c)

or (d,e,f)

 

[CompuChip]

If you just treat them as vectors, then it doesn't really matter.
However, when you are going to do things like matrix multiplication, there is a big difference between row and column vectors.