brain neurons

[jfoldbar]

lately ive been watching quite a few you tube vids about the brain. i find it fascinating. but theres a few things i wonder and cant seem to find answer on google.

 

are brain neurons the same as the neurons in the rest of the body? or are they slightly different? how? any vid you can point me to.

 

what does a neuron "actually" look like. i cant find any "photos" of them only diagrams and animations ect.

every pic i find of them has them as 'like a tree'. so theres the trunk and all the branches. but what about all the space between the branches? what is there?

surely inside the brain cant be mostly space as depicted by every picture i can find of a neuron.