What are custom mechanical keyboards?

Custom keyboards is a wonderful outlet for people to express their own style. From colors to feel and sound, a person can customize their "keebs" the way they want. There are many parts to consider when building a custom mechanical keyboard. The learning curve can vary from easy to hard depending on the parts you choose. There are parts that might require you to solder but also, there are parts that are easy as building Legos. One of the most intimidating part of building a custom keyboard is handing raw technology such as the PCB(printed circuit board). Just as long as handle the parts with care, it's super simple. 
Here's a parts list explaining what each component of a custom keyboard does.

Case: The keyboard case is quite easy to understand. For the purpose of housing all the keyboards components, the case is like the shell for a phone or a case for a computer. A keyboard case comes in many different materials for different purposes. Some are built durable. Some are built with polycarbonate with show off RGB. Some are built heavy so the keyboard won't move. There are many cases out there for you to choose from that accommodates for your needs. 

PCB (Printed circuit board): The PCB is basically the brains of the keyboard. It's what makes the keyboard work. The PCB has it's own aesthetics in it's own right. Something about raw circuit boards is just pleasing to the eye. There are 2 types of PCBs when dealing with custom mechanical keyboards, and they are hotswap boards and solder boards. Each have pros and cons when dealing with them. Hotswap is for ease of use when replacing switches, or just installing switches. Solder boards is tedious to put together but it's more reliable. Here's a pros and cons list about both hotswap and solder boards provided by the custom keyboard community here.

Plate: The plate has the purpose of holding the switches in place. Different plate material will also change the typing experience. Aluminum and brass plates gives the user a firm typing experience while materials like polycarbonate gives the user more flex when typing. 

Stabilizers: Also known as "stabs" by the community, serve the purpose of holding the longer keys in place such as space, enter, shift, and backspace. Stabilizers helps said keys from rocking back and forth allowing you to press them and the whole key presses down.

Switches: Switches are basically the button that activates each key. Let's caveman talk. Finger press switch. switch gets pushed down. Switch contacts PCB. PCB sends command. There are many switches out there that accommodates for every user. From loud clicky switches to silent fast switches. Switches affects the sounds you get when typing. Switches is how you achieve keywords such as "thocc" or "clack".

Keycaps: Keycaps are basically the caps that sit on the switches that have letters, numbers, and symbols. There are many materials for keycaps and this affects how the keyboard sounds and feel. 

Building a keyboard is pretty intimidating but it's not that hard. Building a keyboard is just like putting together some Legos. The beauty of building a mechanical keyboard is that it's your keyboard. You build it the way you want it. 
your own custom keyboard is such a joy. Building a custom keyboard is like making a high class dessert. You put all the ingredients together to create something you love, and it’s yours. You can show off your “high class dessert” and other people can see all the details put into it, giving a feeling of happiness because it’s your creation.