Answer 1

I hope you have some assembly then...
Little endian is completly intel syntax
And
Big endian is completly at&t syntax
so what is different?
well
We want to move 45 to eax register
mov eax,45
intel will move 45 to eax
That is intel order from right to left

while at&t must be like this
movl 45,%eax
At&t will move 45 to eax register
That is at&t order from left to right
However at&t syntax is a lot like C language
with the bracket,comment,parenthesis
So mostly people uses arm as their assembler(used at&t syntax)