Hours of sleep: hacking yourself

But I can manage it but not daily. Your body needs a good rest so that you can do whatever things you needed to do.

it will overall take a toll on your health. even if you get into those "hacked" sleep patterns where you micronap during the day, it is healthier overall to sleep at least 7 hrs.

that said, i normally get 4-5 and devour caffeine during the day

Yes it is possible, you just have to put an alarm to wake you up

YES! My brother was in the Army and for Bootcamp they only got like 4 hours of sleep.

I sleeped at 09:00AM and i woke up at 11:30AM, it wasn't bad actually. ( thanks to my friends, they woked me up )
But in general i'm sleeping at 06:00AM and i'm woking up at 12pm.