You really made me think about it very, verrry hard. And I think i understand now, i don’t type like professional typist, and although i use most of my fingers my left hand is on far left side of keyboard, instead being closer to the middle. If I had my hands on keyboard like I should I would not be using tab key so much probably, because space is much more accessible.
Now I understand why people would use space key for indenting.
