To get started with the Raspberry Pi, here are the things you’ll need for your first Raspberry Pi build.
Table of contents
Introduction
Although the Raspberry Pi comes with all the required features onboard, there are still additional requirements to make it power and boot up into a fully functional computer. This post lists and introduces the 7 requirements and 3 optional requirements you will need for your first Raspberry Pi build.
When it comes to your first Raspberry Pi build, various kits are available, or parts can be obtained individually.
The Raspberry Pi board
At the time of updating this post, there are a couple of Raspberry Pi models and versions available. The latest addition is the Raspberry Pi 4 Model B released in 2019. New models will be added from time to time.

Models can be categorised into the Raspberry Pi A-models, B-models, Compute Models and the Raspberry Pi Zero-models. Versions include version 2 (2015), version 3 (2016) and version 4 (2019).
All the Raspberry Pi B/B+ Models have more or less the same form factor and are about the size of a credit card. All the newer ones also have Ethernet connectivity. I would recommend going with the newest B-models.


2015 Model B

2016 Model B

2016 Model B

2018 Model B+

2019 Model B

2019 Model B
Power supply (power adaptor)
All Raspberry Pi boards need a 5V DC power supply. Important factors when choosing the right power supply include the plug type, connector type and the amount of amperage it can supply.
Plug type
The type of plug used will depend on the wall socket and the country where it is used.
Plugs are typically marked US (United States of America), EU (Europe), AU (Australia), etc. South Africa uses EU standards. Some power supplies, like some of the official Raspberry Pi power supplies, will have plug type adapters.
Apart from being able to connect to the wall socket, the plug type will usually correspond to the voltage output of the wall socket (110V or 220V).
Connector type
The Raspberry Pi 2 and Raspberry Pi 3 models use a Micro-B USB connector. Raspberry Pi 4 models use USB-C connectors.
Power output
The amperage (amps in short) will determine the amount of power (in Watts) that can be delivered to the Raspberry Pi. The total amperage required depends on what and how many peripherals are hooked up to it.

The Raspberry Pi foundation recommends a power supply that is capable of supplying at least 1.2A (1 200mA). More is better. Typically, power supplies that can supply 2-3A are popularly used, especially when USB peripherals are connected.

For Raspberry Pi 2/3

For Raspberry Pi 2/3

For Raspberry Pi 4
MicroSD card
As with all computers, the Raspberry Pi board needs primary storage space. This is where the operating system (see later) and files are stored. Additional space can be added later on. The Raspberry Pi comes standard with a MicroSD card slot.

The guys at RaspberryPi.org recommend a MicroSD card with at least 8GB of space. 16GB and 32GB MicroSD cards are also available but come at a higher price.
Smaller operating systems, such as RetroPie can be installed on a 4GB card, but more is better. Larger SD cards will allow additional storage on the Raspberry Pi.
Irrespective the size of the MicroSD card, it is recommended to get hold of the fastest card available, e.g. Class 10 or faster.
Because MicroSD cards are fairly cheap and easily interchangeable, it is recommended to get a few at the same time.

Online shops, such as Amazon.com, often have great discounts on MicroSD cards under their camera sections. Although not always the case, BangGood might have some deals on generic MicroSD cards that are worth their price.

SDSQUA4-032G-GN6MA, UHS-I/Class 10

MB-ME32GA/AM, Class 10
MicroSD card reader
A MicroSD card reader is needed to copy the operating system from a PC onto the MicroSD card. Card readers are also typically used to transfer photo files from a camera to a desktop. If you don’t already have a built-in card reader on a desktop or laptop, you will need an external card reader.
External SD card readers are connected to a desktop/laptop via one of the USB ports. If used correctly, the desktop operating system will connect the card reader as one of its drives.

There are many options available. Some card readers will only be able to read SD/MicroSD cards, while others have slots for a variety of card sizes. Some Raspberry Pi Kits will include a MicroSD card reader.
My experience with the HAMA External USB 2.0 Card Reader has been a good one. BangGood also offers a range of cheaper card readers.

Operating system (OS)
The Raspberry Pi board will need commands to function. The commands are determined by the operating system (OS) which is copied onto the MicroSD card.
Most of the popular operating systems are Linux-based, incl. Raspbian (now also known as Raspberry PI OS), OpenELEC, RetroPie, etc. Although there are many certified Raspberry Pi operating systems available, Raspbian is probably one of the better ones for beginners.

Most of the better, certified Raspberry Pi operating systems are open source and free to download.
Generally speaking, operating systems are copied onto a MicroSD card as a .img file.
Keyboard & mouse
Peripherals, such as a keyboard and mouse, can be connected via the Raspberry Pi’s multiple USB ports. The most basic peripheral needed is a keyboard, but for graphic user interface (GUI) users, a USB mouse is also a must.

Any new or old USB keyboard and mouse will do. Out of the box, the Raspberry Pi is also capable of using a wireless keyboard and mouse. These peripherals can be obtained fairly cheaply from Amazon.com or BangGood.
The HDMI cable & screen
From the second generation, the Raspberry Pi started using High-Definition Multimedia Interface (HDMI) ports. The Raspberry Pi 4B started using Micro-HDMI output. Starting with the second generation Raspberry Pi boards, there are only a High-Definition Multimedia Interface (HDMI) connection port to connect to a screen.

The screen can be anything from an old PC monitor to a flatscreen TV. If a screen does not have an HDMI input, various connectors are available to make it work.
HDMI cables and screens are available from local PC shops, Amazon.com and BangGood.
Optional requirements
While most of a Raspberry Pi’s functionality can be used with the previous requirements, there are some optional requirements. They include a network cable, a Raspberry Pi case and a USB Wi-Fi dongle.
Network cable
Being able to connect a Raspberry Pi board to a network (or the internet) significantly increases its functionality. Although, technically, not a requirement, it definitely comes highly recommended.

The Raspberry Pi has an Ethernet port, ready to connect to a local area network (LAN). A wired network will be faster and more stable when compared with Wi-Fi.
Any standard Ethernet cat5/cat6 cable can be used. Ethernet cables can either be bought as required or can be cut to length and assembled. Various types and lengths are available online from shops such as Amazon.com and BangGood.
The Raspberry Pi models 3 and 4 can also be connected to a Wi-Fi network in almost no time. Earlier models will need a USB Wi-Fi dongle (see later).

Cat6. 2m, 3m, 5m or 10m
Raspberry Pi case
Just like any computer, the Raspberry Pi board needs some protection. Apart from this, the case is also something to show off with or to make the Raspberry Pi fit into its surroundings.

When it comes to Raspberry Pi cases, there are many types, shapes, colours and form variations available. One thing to look out for is to make sure the case is designed for the model used. Raspberry Pi Models B+, 2B and 3B/B+ can use the same case while Model 4B needs its own.
Amazon.com has a nice variation of Raspberry Pi cases available. Seeing that the Raspberry Pi case is generally just a piece of plastic, nice, cheaper generic cases can also be ordered from BangGood.
USB Wi-Fi dongle
In the case of a Raspberry Pi model 2B (or earlier), a USB Wi-Fi dongle can be used to connect wirelessly. Various USB Wi-Fi dongles are available and most of them should be compatible with the Raspberry Pi. Many generic Wi-Fi dongles are available at cheaper prices.




Generic versions are also available from BangGood.
Raspberry Pi Kits

2019 Model B, 4GB RAM

2019 Model B, 8GB RAM

2019 Model B, 4GB RAM
Conclusion
New Raspberry Pi users can either start off with a kit or collect individual parts separately. This post listed and discussed the individual requirements for your first Raspberry Pi build.