The motherboard - part of the computer where such things as the processor, memory modules, expansion cards and external devices are attached. It controls the functions of different components. The number of connection slots for peripheral devices and the number and type of memory slots are important properties of the motherboard.

In addition to the various connections, the motherboard also has a small battery ensuring that settings made on the board are retained even when the computer is switched off.

The processor - The processor can be considered to be the ‘engine’ of the computer because it executes the lion’s share of the information processing; the processor fetches commands and necessary information from the RAM, carries out the tasks specified by the commands, and returns the processed information to the RAM. The speed of a computer depends largely on the speed of the processor.

Random access memory - The RAM (Random Access Memory) is a memory storage that functions during computer use and is especially utilised by the processor. In modern computers, the amount of RAM is around 4 – 16 GB depending on the type and purpose of the computer The RAM consists of one or more memory modules. If there is enough RAM, the computer executes requested tasks quickly. This is why it is a good idea to add to the memory by buying more memory modules as the need arises.

Hard drive - The hard drive is the permanent memory of the computer where saved files remain even when the computer is turned off. This is why the hard drive is used for saving files.

The capacity of hard drives varies; currently the typical capacity is 500-1000 GB, but hard drives of over 1500 GB, i.e. 1,5 terabite, are also available. However, the capacity of the internal hard drives in laptop computers is often less than that

Hard disk - It is used for the storage of the computer’s operating system and all important files. It is therefore packed in a fixed protective housing. The disks may become damaged in spite of this protection, so you should absolutely make backup copies of files on the hard drive from time to time.

DVD and Blu-ray drives with writing capabilities - Most computers these days come with a Blu-ray drive or a DVD (Digital Versatile Disk) drive with writing capabilities, with which you can burn such things as backup copies of important files to DVDs. CD drives are older and have mostly been replaced with DVD drives. CD drives can only burn data on CDs, which have a substantially smaller storage capacity, while DVD drives can burn data to both CDs and DVDs with more capacity.

The display and display adapter - Most computer displays are so-called LCD displays (Liquid Crystal Display), where the image display is produced by liquid crystals between two transparent sheets. Display sizes range between only a few inches in handheld apparatuses to large 24 inch desktop displays.

One of the most important features of the display is its resolution, i.e. how many pixels (picture elements) the image consists of.  A normal 22 to 24-inch widescreen display usually has 1920 pixels horizontally and 1200 pixels vertically (1920×1200). These displays can reproduce FullHD (full high definition) image.

Keyboard - A standard keyboard has 102 keys. The keys are divided into alphabetical (a-z), numerical (1-0) and special (Function, Ctrl, Alt etc keys).

In addition to the usual alphabetical and numerical keys, you should know at least the following special keys that are located among the alphabetical ones.