I was always taught with them horizontal: I guess either makes sense (at least in L to R reading countries), and am curious about the difference.

I, too, was irked by the claim that you could just connect the diode across from ground to power, though: good way to blow your diode, that. And yeah, the hydraulic explanation of voltage was a little opaque, but ultimately unnecessary anyway for anything other than the diode resistor.

Quoting http://en.wikipedia.org/wiki/Electric_current:
“[...] in metals where the charge carriers (electrons) are negative,
conventional current flows in the opposite direction as the electrons.”

Current is always from more positive to more negative electric potential, by definition (convention).

http://en.wikipedia.org/wiki/Electric_current

http://www.youtube.com/watch?v=AOqfWj0HqNE

One quibble I have (and someone already pointed it out Jody in a commnent on her blog) is page 4: voltage (AKA Potential) is more like pressure than ‘speed of flow’ – voltage is still present even when there’s no flow.

Actually, make that two, no, three more quibbles:

On page 5: I wish she had drawn a hand pushing down on the container of water and kept the width of the hose/flow the same to show ‘increase the potential/voltage/pressure, increase the flow’.  As it stands, the drawing shows ‘increase the current, increase the flow’ – which is also true.

Lower down on the page: I realize that the PDF is meant as a let’s-not-scare-the-kiddies away from using an Arduino, but the current doesn’t flow from the positive to the negative poles of the battery. 

Yes, sadly, your high school physics teacher is still right.

Current flows in the opposite direction of the Voltage.    She should remove the inside-arrowed part of the schematic – it just doesn’t belong in a schematic anyway.

Page 3: Discrete information can be in more that two states.  Easy to grok example: Integers.  Integers are discrete numbers.   And…

ANY counting system which is unbounded can have an infinite amount of
states, even binary numbers.  As for analog information always having an
infinite number of possible values, Max Planck and about a million
quantum physicists would like to have a word with you…

Page 10: the longer leg on a diode doesn’t ‘connect to power’.  It connects to the (more) positive voltage.  It’s quite possible to connect the shorter leg to a negative voltage supply and connect the longer leg to a Ground.  I also wish she had explained roughly WHY you have to put a 220 ohm resistor between a 5V supply and the LED.  The exercise of why you have to use a different value of resistance if the LED is connected to a 12V power supply can be left as an exercise for the reader.

There’s another small error, but I’ll just leave it as an exercise for the readers.

Yes, the devil is in the details…

Each new person explaining me basic stuff hurted my brain.

Every attempt to give cute explanations in silly ways just to make me understand better have failed miserably to catch my attention and to figure out what all this mess meant because as soon as it gets interesting – it’s not because I don’t understand that I don’t find it interesting – it gets complicated and usually goes straightforward at an insane speed, not giving me the time to ask stupid questions to get obvious answers. No matter how much I read it, it never makes sense and yet everyone else manages to grasp the meaning of this psyché rock world.
Since then, I’ve always avoided the topic but also admired people who make nice stuff with a few things and basic knowledge of electronics.

So if you found yourself in my description above, if like me you always attempted to dive into this interesting world of electronics but always feared it because you never understood anything at even the simplest tutorials, I recommend you to read this PDF. Do read the comic that makes things easier to understand, and be forever “stuck” at page 4, 5, 6… like you’ve always been – ah those infamous electricity terms, and the worst is, those terms are “basics”. :)

I’m mostly kidding, but I sincerely appreciate the efforts of the Arduino project(s) and I like this nice introduction to Arduino with simple explanations. I’ll try again another time ;)

… could an LED cube be in my future?