Why do i need an Easydriver to control a Stepper Motor?

Hello, I am fairly new to Arduino and electronics, so please don't go too hard on me.

I have the 28BYJ-48 Stepper Motor and wanted to connect it to the Arduino and just test it and maybe build something using it.
I looked online for tutorials and Schematics and found very many using an Easydriver.
I didn't understand why and couldn't find any explanation. The most helpful thing I found was somebody using a L293DNE...
I don't know how the Easydriver or the L293DNE work and what function they have.

I also have another small point:
I saw all using an external battery.. and I have 2 problems with that.

  1. Why? What is the reason behind not using the power from the Arduino?
  2. I don't have a "Battery to Board connector" is there an easy solution? or is the best thing to buy one?

First, the Arduino can only output 20mA on a pin. That's enough to light up an LED but it won't turn a motor.

Second, stepper motors need special drive electronics to get the best performance. You can drive them with "simple" drivers like the L293 but you're pulling a Ferrari with a horse. Pololu in the US makes some really good drivers. Buy some of them.

  1. The 5V rail on the Arduino can't deliver a lot of power. If it's powered from USB then 500mA is all you can get (safely.) A couple of AA batteries can give you many amps, although not for a very long time.

  2. Yes. But if you're considering a stepper motor project then batteries won't last very long, even when the motor isn't turning.

Thanks MorganS for the quick and very helpful answer, but I still have one question.
What is the right thing to buy? Is it an Easydriver or the L293? Or is it the same concept?
Because I saw 9/10 using a red EasyMotor and 1/10 using the L293.

Yes, the Easydriver is good for steppers. I've never used one, but the specifications look good.

One last and specific question.
What. Is. This?
I saw someone using it.

The isn't working so I am using a link

https://picload.org/view/dggrooal/whatisthis.png.html

OPs image inlined.

whatisthis.png

Looks like a regulated power supply to me.
Edit: Yup.
http://artofcircuits.com/product/mb102-breadboard-power-supply-module-3-3v5v

Lorus:
I have the 28BYJ-48 Stepper Motor and wanted to connect it to the Arduino and just test it and maybe build something using it.
I looked online for tutorials and Schematics and found very many using an Easydriver.

That is a Unipolar stepper motor and the usual driver is a ULN2003. There must be hundreds of Forum Threads about 28BYJ motors.

The Easydriver is for Bipolar stepper motors.

...R

Here's a ULN2003 module for the 28BYJ -48.
https://www.amazon.com/XO-Stepper-ULN2003-Circuit-4-Phase/dp/B01MTFPBPE/ref=sr_1_5?ie=UTF8&qid=1504648778&sr=8-5&keywords=uln2003

Steppers come in 4, 5, 6 and 8 wire varieties:

4 wire - bipolar only
5 wire - unipolar only
6 wire - bipolar or unipolar
8 wire - bipolar (2 possible impedances in 4:1 ratio) and unipolar.