Proxy server is a computer which mediates between net surfers and information on the Internet. When connecting the user's computer to the proxy server, all requests of its programs and applications are received by the proxy server, and only after that they are sent to the global network. This allows the user to remain anonymous, because requests do not come with its ip-address, but with the address of the proxy server. Also, the proxy server may use the cached information, thus increasing the speed of processing user requests.

Firewall is software, which is responsible for the system protection. Its main function is to guard the user's computer from any malicious actions, as well as notification of violations in the system.

Root (superuser) is a special user account which has the exclusive functions. Usually root account owns main administrator of the website which often is its creator. It allows him to make any changes and generally to execute all possible operations.

SSH is a network protocol that allows you to control the programs of the operating system remotely. It ensures the safety of the data, as the entire flow of information, including passwords is encrypted. You can also transfer video and audio streams over an encrypted channel.

Port (port speed) is an identification number (from 1 to 65535) for a network application. In case of an information exchange session, especially in case of simultaneous operation of several network applications, the correct direction is determined by this number for data transfer. Port speed is the speed at which a particular port can accept or send information.

Operation system is a collection of control and processing computer programs (PC, notebook, smartphone etc.). Every part of OS has its name. The kernel of OS controls the computer hardware resources and also is responsible for execution of programs. The file system provides information storage. The interpreter is responsible for interaction of the user with the device. OS also has a lot of utilities. With operating systems you can control both programs (user interface), and the hardware and software resources.

Uptime is an amount of time the server was working without any glitches and interruptions. This criterion is very important when choosing a hosting provider. It shows how reliable the hosting server is. The longer uptime lasts the longer client’s website will be available for users.

Hard drive is an external storage device that provides data storage in a computer. The information is written on the hard disk magnetically and is consistent. Hard drive is a drive of random access. It helps to find any information section for the same time period. It means that the data reading, written later, requires the same amount of time, as for reading information which was written earlier.

Random access memory is a part of a complex computer memory system.  It temporarily stores information which is needed to the CPU for executing commands. In case of switch-off of a supply of the computer all data from a random access memory are erased.

Processor is a chip or system of chips; a computer device which defines its main opportunities for processing and storage of data arriving in the form of a digital code. The processor has all the electronic computer components (computer bus, video card etc.). Computer has main processor which controls the work of memory and computer bus and executes an object code.