PS4 or XBox One?

I want to get a new video game console, but am torn between getting the PS4 or the XBox One. I don't know much about either one, and hoped you guys could help me decide.

I have a history with PlayStation, since that is the only brand I have ever owned (I've had a PS1, PSone, PS2, and a PSP), so I'm already inclined to get a PS4 simply because I am already comfortable with the PlayStation brand, as well as the game controls and the buttons on the controller. However, I know nothing about the XBox brand, and don't want to get a PS4 if there is a chance I would regret it later.

I want to know as much as possible about each console, but don't know where to get the information. Please tell me as much as you can, preferably in a non-biased way, or as non-biased as you can be. Also, I have one specific question that I would like answered: Can I play PS1, PS2, and PS3 games on a PS4?

Thanks in advance to all those that help me, it is greatly appreciated.

Ps4. The graphics card is better, the memory cards hold more space, and the fps is WAY higher. It also has a lag spike reduced build in. Xbox one has none of these, or not as much.

No you can only play ps4 like the ps3 you would think this would be a thing they would add to allow it to but no they couldnt make it that easy

But found the ps4 good until 3-4weeks after I got it the power supply shat its self googled it and its very common some fault in the unit or something rather but yeah ps4 was good is good if you dont mind sending it away to get fix