What is a Monitor? Types of Computer Monitors Explained

Computer monitors have evolved over the years and image quality has followed suit. In this article, we will explain what a monitor is and the different types you can get.

We will also explain more about the various types and how they get connected to a computer. The connectors also evolve so they can keep up with the demands of newer display technology.

What is a monitor?

computer monitor

A monitor is a display device like a TV screen, that interprets and displays the graphical output signal from your computer’s graphics card and displays it on the screen.

This enables you to view the display interface in order to interact with the computer using various peripherals like a mouse or keyboard.

To have a better understanding of what a monitor is, knowing about the different types is beneficial.

Different types of monitors

Display technology in various applications has evolved sharing the same base technology.

Both the television and computer screen started using the vacuum CRT (Cathode Ray Tube).

CRT Monitors

crt monitor

This type of monitor required more power and electronics to operate. A lot of the analog circuitry was cumbersome and took up a lot of space.

In addition to that, the CRT itself requires a certain distance between the screen area and the electron guns located at the end of the neck.

So apart from being heavy, bulky, and harsh on your eyes, they actually have a decent viewing angle.

The other obvious downfall is the obvious fact that it couldn’t be used for a laptop monitor.

LCD Monitors

lcd monitor

LCD Monitors replaced the CRT. Initially, they had performance issues to do with response times, but eventually, those problems were solved.

Liquid crystal molecules are placed between two electrodes. The amount of light that can pass through the liquid crystal molecules is determined by the amount of electrical charge applied to the electrodes.

LCD Monitors require backlighting in order to illuminate the image for us to see. This backlighting technology has also undergone some revolutionary changes.

In the beginning, CFL(Compact Fluorescent Lamps) were used. The inverter boards that stepped up the voltage in order to power them up, were unreliable.

Thankfully, the CFLs were replaced with LEDs. This made LCD monitors way more reliable.

We will go into the various backlight technologies further down in this article.

Common types of Active Matrix LCD panels:

IPS Panels

In-Plane Switching panels were created to solve the poor viewing angles and low-quality color of the TN panels.

They are more commonly used in professional environments because the refresh rates aren’t the best for gaming.

But when it comes to image quality, it delivers great results. And, it comes with a little extra on the price.

The response times are faster than VA panels but slower than the TN panels.

TN Panels

Twisted Nematic panels are the most commonly purchased by consumers. They deliver reasonable response times at a reasonable price.

LED Monitors

Light Emitting Diode monitors are essentially LCD screens with LED backlighting to illuminate the LCD image.

Personally, I’m not a fan of this name for this type of product. If it is truly an LED monitor, shouldn’t the pixels themselves be produced by an LED itself?

Although, that technology is on its way. Television manufacturers are putting their interest in micro-LEDs. This is where microscopic LEDs are placed in an array to form the pixel itself.

I have no doubt that this technology will make its way into computer monitors.

QLED Monitors

QLEDs or Quantum Dot Displays are used to convert the backlight to emit pure basic colors.

These semiconductor nanocrystals are placed in a Quantum Dot layer in order to help RGB color filters by reducing light losses and color crosstalk.

Electro-emissive versions are in their experimentation stages. This means, by applying an electric current to inorganic nano-particles, a pixel is formed by a Quantum-Dot Light Emitting Diode (QD-LED).

This would allow for great color ranges and near-perfect black levels on the display.

Different types of video connectors

Here are some typical video input connectors you will find on the back of computer monitors.

These connections allow your monitor to connect up to your computer’s graphics card in order to have the display information.


a VGA connector up close

Video Graphics Array is a technology that is obsolete. It has been around for a long time, but an analog video signal is no longer the desired standard. It is not able to carry an audio signal.


a male DVI plug that connects to a monitor or graphics card

Digital Visual Interface is a digital video signal connector that is used not only in computer monitors but in other consumer electronics too.

Dual-link DVI carries twice the data rate compared with that of single-link DVI. This has allowed for higher resolutions and refresh rates.

Dual-link has a maximum data of 9.90Gbit/s @ 165 MHz.

No audio signal can be carried over this connection.


an HDMI connector closeup shot

There are 5 types of High-Definition Multimedia Interface connectors:

  • Standard (A)
  • Dual-Link (B)
  • Mini (C)
  • Micro (D)
  • Automotive (E).

This is a replacement for analog video standards and can transmit uncompressed video data and compressed/uncompressed audio data.

Incremental versions have arrived over time with improvements.

HDMI is used in a broad variety of consumer electronics, even when it comes to computers.

Version 2.1 is capable of delivering a maximum total data rate of 42.5Gbit/s.


a display port connector close up

DisplayPort is more commonly used in the computer market, rather than in general consumer electronics.

The latest version 2.0 has a maximum total data rate of 77.37Gbits/s.

DisplayPort comes in two sizes, the standard size, and a Mini DisplayPort.


a thunderbolt plug closeup

The previous versions (v1 and v2) use the same connector as a Mini DisplayPort.

The latest Thunderbolt version 3, uses a standard USB C connector.

Thunderbolt combines PCI Express and DisplayPort into 2 serial signals and provides DC power.


a usb type c connector up close

USB C Monitors are quite new to the market and tend to be a popular trend for mobile monitors.

You will most likely need a cable that can connect your monitor from USB C to Display Port or HDMI for example.

Two different styles of power connectors

power brick or power supply for monitor
iec power plug inlet monitor

Some monitors are built with internal power supplies, and others rely on external power bricks.

Those with an internal power supply, usually require a power cable that goes straight from the mains power to an IEC plug that plugs directly into the back of the monitor.

For displays that require an external power supply, power goes from the wall socket into the power brick.

The power brick steps down and converts the mains supply to DC. It is very common for the monitor to run off 12 Volts DC.

While the external power brick makes life a bit harder when it comes to cable management or keeping things tidier, it has one major advantage.

Quite often monitors go faulty because of a fault in the power supply. It’s way easier and cheaper to replace a common power brick than to get the whole screen repaired or replaced.

The advantage is that by having components crammed inside the monitor, the internal operating temperature should be reduced.

Aspect Ratios

The aspect ratio is the horizontal width of the display with respect to the vertical height.

Different types of aspect ratios are used for different applications.

Multi-Monitor Arrangements

Computer graphics cards have the capability to output to multiple monitors at once and span the display across them to treat them as a single one.

This is particularly nice for gaming.


For some types of professionals, monitors are physically rotated 90 degrees so that the screen is vertically taller than wide.

One example is to help computer programmers see more code at once. Not all programmers do this, just thought I’d mention that.

Some monitor models have this capability built into them, so no modifications are necessary.


The resolution is specified by the number of pixels starting with horizontal followed by vertical.

For example, 1024×768 means that the resolution contains 1024 pixels in width and 768 pixels in height.

Pixel pitch

Pixel pitch is the amount of space between each pixel. This has a big impact on the quality of an image on a screen.

If the pixel pitch is too large, it won’t matter how high the resolution of your monitor is, the image will be poor.

Refresh rate

The refresh rate is the number of times the entire screen can be updated per second.

For example, if the screen has a 60Hz refresh rate, the screen is able to be fully drawn 60 times in one second.

These days, a 144Hz monitor is quite common and doesn’t cost nearly as much anymore.

Response Time

This is the rate at which a pixel can be changed from black to white or from one shade of grey to another.

While you can count the rate at which other color shades of pixels change, black, grey, and white are most the extreme opposites in contrast with respect to each other.

Therefore, they will be noticed first.

Response time is usually written on the millisecond scale.

Good response times are anything starting at 5ms or faster.

Curved displays

an example of a curved computer monitor

There are pros and cons to curved displays. In my opinion, you need to try one out to see if it’s something for you or not.

These curved monitors can offer a slightly more immersive experience when it comes to gaming, but they are a bit more expensive compared to ordinary flat ones.

Power consumption

Power consumption has been reduced considerably since CRT displays have fallen away.

Now, a common desktop monitor consumes between 60 and 250 watts of power. In standby mode, roughly between 1 and 6 watts.


And there you have it. You know what a monitor is, and more than that, what the different types are.

I hope you enjoyed the information and knowing more about them.