What Is Resolution? The Basics Explained Simply

Haru

When you start learning about resolution, the complexity can feel a bit overwhelming. Let me start by explaining the basic concept of what resolution actually is, in simple terms.

First, let’s understand pixels

A pixel — short for “picture element” — is a tiny dot that makes up an image.
Pixels of various colors come together to form the images we see.

A photo of a cat sleeping on a pink blanket. A circular area is magnified, showing that the image is made up of small square pixels.

What is resolution?

It refers to the level of detail in an image.
In other words, it indicates how densely pixels are packed into an image.

ppi/dpi are units of resolution

ppi (pixels per inch)
dpi (dots per inch)
These are units used to express image resolution.
*Technically, ppi is used for digital resolution and dpi for print output resolution, but they mean the same thing, so you don’t need to worry about using them strictly.

They indicate how many pixels (dots) are lined up along one inch (25.4 mm).

A diagram comparing pixel density at 10 ppi and 30 ppi. On the left, 10 ppi is shown with a coarse 10×10 grid. On the right, 30 ppi is shown with a finer 30×30 grid, illustrating that higher values mean greater density.

The higher the number, the greater the density and the sharper the image

I’ve prepared the same image at three different resolutions: 30, 72, and 300 ppi.
Even though the size is the same, the one with more pixels naturally looks more detailed and sharper.

Three copies of the same illustration of a girl eating watermelon, compared at different resolutions. The left one at 30 ppi is rough and pixelated, the center is at 72 ppi, and the right at 300 ppi is sharp and clear.

Summary

Resolution is about how densely pixels are packed into an image.
The more densely packed they are, the more detailed and sharper the image looks.
ppi/dpi are units of resolution — 300 ppi means 300 pixels are lined up along one inch.

#printing #resolution