Deciding On Which Application To Learn first, Photoshop Or Illustrator?
Photoshop & Illustrator are common application for graphics design & other things, learning any of them cannot just give you a boost in graphics design. But it can look good in your resume. Deciding on which one of the two you want to work on depends on what you want to create the most.
Quickly go to:-
So, What’s The Difference Between Photoshop & Illustrator?
The main difference between Photoshop & Illustrator is the kind of graphics each application creates, Photoshop creates raster graphics, while Illustrator creates vector. In case you don’t know what that means, don’t worry, as I will talk about them right away.
What Is Raster Graphics
Raster graphics is the kind of graphics where the image is created by having small squares, called pixels, arranged side by side. The computer memorized the arrangement of these pixels & uses that to display the picture. Like this:-

Raster graphics has one key disadvantage, since the pixels are memorized by the computer, it can’t be enlarged without losing some of the quality. There are many techniques where the computer try to produce additional pixels to create a bigger picture, but there’s a great limit to how much you could resize the picture without losing much quality. So having a large enough picture from the beginning, either by drawing on a big canvas, or to by taking picture with a camera with high resolution is a must. It is not uncommon to have pictures larger than what you need too.
As I previously said, Photoshop is mainly made for creating & editing raster graphics.
Okay, What About Vector Graphics?
On the other hand, Vector graphics are created using mathematical equations. If you have a line drawn that way, every time the application displays the line, it redraws the line from scratch using the equation it has in memory. This gives vector graphics a huge advantage over raster, no matter how you zoom in or enlarge the picture, and no matter how large the paper you want to print the image on is, vector graphics will never fail you here.
Here’s how an image would look like in case it was zoomed in both raster & vector graphics:-

Since the equation of the object (the line in this case) is simple & short, vector graphics tend to take much less space compared to raster graphics.
That being said, you may be thinking that vector graphics should be used all the way. That may be the case in some cases. But vector graphics has some disadvantages too, like how you can’t use it to create complex images.
You should learn Illustrator in case you want to create vector graphics.

And Finally
Both Photoshop or Illustrator have the capability of the other one. Photoshop can create paths, which are vectors, while Illustrator can have raster objects that can’t be resized. But it is totally better to use each application for their intended use, rather than use one for everything.
I hope this post made it easier to you to chose whether you should learn Photoshop or Illustrator. :>
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