Computer hardware and software

computer hardware and software
Every computer is composed of two basic components: hardware and software. hardware includes the Physical features, which are every part that you can either see or touch, for example: monitor, case, keyboard, mouse, and printer. The part which activates the physical components called software. it includes the features that responsible for directing the work to the hardware.

von-Neumann architecture of the computer
according to it there is a general structure that a computer's hardware programming and data should follow. it contain few components, for example, the first and primary used is the Input. Which is every hardware feather that using to insert orders to the software. E.g. keyboard.

How the von-Neumann architecture works? Step 1- send data and program to main memory through input device Step 2- control unit read from memory Step 3- control unit send instruction to ALU and then read data from memory to ALU Step 4- ALU store the result Step 5- output result from memory to output device Harvard architecture is modern than von Neumann architecture which allows the computer to read data faster and more effectively, in a way that von Neumann architecture is incapable of. The main differences between the two types of computer architecture are related to the functioning of the central processing unit.

Memory
memory unit is divided to two types of register: MDR-The register of a computer's control unit that has the data to be stored in the computer storage e.g. RAM. MAR-has both memory address of data and memory address of instructions. The function of this specific register is to access data and instructions from the memory. Processing unit- composed of a units which process the orders. One of them is the ALU-arithmetic logical unit that prefoemes two typed of orders: 1.    Mathematical operations (+,-) 2.    Logical operations (=,<,>)

Control unit- Unit that bring the instruction from memory to be executed and decodes. CPU- central processing unit. Has the instructions of a computer program by presenting the basic arithmetic, logical, control and input/output. CPU composed of ALU (arithmetic logical unit) and CU (control unit). Output unit- Hardware which performs the result of the instruction.

RAM
Is random acsses memory, keeps the data and general purpose program that the compter executes. RAM is not permanent, its contain can be changed and it is erased when the computer is off.

Storing device
any hardware that can hold information, temporarily or permanently. we distinguish two types of storage: a primary storage device (RAM), and a secondary storage device (hard drive). Secondary storage can be removable, internal, or external storage.

Examples of computer storage: 1.	Magnetic storage deviced- for example: hard drive, floppy diskette etc. 2.	Optical- example: blu-ray disc, CD-rom disc etc. 3.	Flash memory devices- memory card,memory stick. 4.	Online and cloud- cloud storage, network media. 5.	Paper storage- OMR, punch card. Today the most storage devices are hard disc drive or SSD.

motherboard
is the physical arrangement in a computer that contains the computer's basic circuitry and components. It has a socket for the CPU, RAM and expansion part (sound cards, graphic cards ETC) and also connects together the CPU, memory, hard drives, optical drives, video card and more. To activate a computer there Is a need in an operating system. (OS) is system software that manages computer hardware and software resources and provides common services for computer programs. All computer programs require an operating system to function. Operating system controls computer's hardware, run the computer's programs and orgenizes files. The programs that we use on everyday base called an application program. app is a computer program designed to perform a group of coordinated functions, tasks, or activities for the benefit of the user. E.g. ppt, excel, word.

Bits and bytes
Bits- are the smallest storage units in the computer. A bit can store just 0 or 1, which is called binary, and therefore can be stored by physical devices or systems that has two separate states. For example 2 positions, or states of an electrical switch, the two states being ‘on‘ and ‘off‘. A bit can also be described as true/ false, no/ yes etc. Notice that a bit has only two coding options, or 2 values. One bit is too small to be used, and thus computers use a larger storage unit called bytes. Bytes- are made of bits. 8 bits are used to create 1 byte. 1 byte can store 1 letter, character or symbol, such as the letter ‘a‘, the number ‘6‘ or the symbol ‘@‘, meaning 1 byte has only 1 possible value. The letter ‘a‘ for example, is one byte, which is made by the combination of 01000001, and each number is 1 bit. RAM, hard drives and flash drives, are all types of storages measured by bytes. Other storage units: 1 KB (kilobytes)= 1024 bytes 1 MB (megabytes)= 1024 KB 1 GB (gigabyte)= 1024 MB 1 TB (terabyte)= 1024 GB 1 PB (petabyte)= 1024 TB Each storage unit is made of the smaller units, and the basic one composing all is the bit.

data
is any set of characters that has been gathered and translated for some purpose, usually analysis. It can be any character, including text and numbers, pictures, sound, or video. If data is not put into context, it doesn't do anything to a human or computer. Within a computer's storage, data is a collection of numbers represented as bytes that are in turn composed of bits (binary digits) that can have the value one or zero. Data is processed by the CPU, which uses logical operations to produce new data (output) from source data (input).

Information
can be encoded into various forms for transmission and interpretation (for example, information may be encoded into a sequence of signs, or transmitted via a sequence of signals). The bit is a typical unit of information, but other units such as the nat may be used. Example: information in one "fair" coin ﬂip: log2(2/1) = 1 bit, and in two fair coin flips is log2(4/1) = 2 bits.

Knowledge
is a familiarity, awareness or understanding of someone or something, such as facts, information, descriptions or skills, which is acquired through experience or education by perceiving, discovering, or learning. Knowledge can refer to a theoretical or practical understanding of a subject.

algorithm
An algorithm (pronounced AL-go-rith-um) is a procedure or formula for solving a problem, based on conducting a sequence of specified actions. A computer program can be viewed as an elaborate algorithm. In mathematics and computer science, an algorithm usually means a small procedure that solves a recurrent problem.