0:02 welcome to learn computerscience
0:04 online.com and in this video we are
0:08 going to discuss how computer works this
0:10 video tutorial is specially designed for
0:12 absolute beginners who wish to get
0:14 familiar with the basic working of a
0:17 computer system from the moment you
0:19 press that power button to the seamless
0:21 operation of your favorite software
0:24 computers perform a complex operation of
0:27 hardware and software to make it all
0:29 happen but before we dive into the
0:31 intricate of working of a computer let
0:34 us first get familiar some fundamental
0:36 concepts and basic knowledge that will
0:38 help you easily understand how computer
0:41 works let us start with a brief
0:43 introduction to computer a computer is
0:46 an electronic device that consists of
0:49 hardware and software components the
0:51 main task of the computer is to execute
0:53 a program that provides the desired
0:57 functionality to the user in computer
0:59 the hardware parts perform the desired
1:02 task as for the instructions provided by
1:04 the software it is the software that
1:07 directs the computer hardware to perform
1:10 a specific operation a computer program
1:12 consists of set of instructions in
1:15 binary called the machine instructions
1:18 the computer understands only binary
1:21 which is a language of zeros and ones
1:23 however the programmers write the code
1:26 in high language which gets compiled to
1:28 low-level machine instructions in binary
1:31 that computer can d directly execute the
1:34 computer hardware components can broadly
1:36 be grouped into four basic types based
1:37 on their
1:40 functionality let me explain this with
1:43 the help of a computer block diagram the
1:46 computer's four functional units include
1:49 first input devices second the central
1:52 processing unit also called a
1:55 microprocessor third a memory unit which
1:57 is used for storing the data and the
2:00 fourth output devices used to present
2:04 the data to the user all right so far we
2:06 have covered the hardware and software
2:09 part let us now get introduced to
2:11 another important element of a computer
2:14 that is an operating system an operating
2:17 system is a type of system software and
2:19 the overall in charge of the computer
2:21 that performs some of the most important
2:24 functions a system software is
2:26 internally used by the computer to
2:28 perform some crucial functions and to
2:30 operate various Hardware devices deves
2:33 connected to the system every Computing
2:35 device needs an operating system to
2:38 operate and interact with a computer an
2:41 operating system is an indispensable
2:44 component of every computer it performs
2:46 some of the most crucial functions
2:49 necessary for the computer to work
2:52 properly Microsoft Windows and iOS for
2:54 the Apple computers are some of the
2:57 common examples of operating systems let
3:00 us now move on to our next topic that is
3:03 an application software a computer also
3:06 needs an application software popularly
3:09 called as apps application software are
3:11 the computer programs that are designed
3:14 to provide a specific functionality to
3:18 the user for example Microsoft Word is a
3:20 type of application software that is
3:23 extensively used for the document
3:26 creation similarly a video game that we
3:28 play on computer is also a type of
3:31 application program in simple words
3:33 whatever you wish to use the computer
3:35 you will need an application software to
3:39 perform this task all right so far we
3:42 have discussed some fundamental concepts
3:45 essential to understand the computer
3:47 operations let us now dive into our main
3:50 topic that is how computer works from
3:52 the start till the end when it is
3:55 powered off when we switch on the
3:57 computer it is the BIOS that gets
4:00 activated first the bi bios is a type of
4:03 miniature operating system called a
4:06 firmware the BIOS performs four
4:08 functions it will first check the
4:10 computer hardware this test is called
4:15 power on self test abbreviated as post
4:17 second it will initialize the hardware
4:20 third it will search and load the main
4:23 operating system and finally it will
4:25 hand over system control to the main
4:28 operating system the user can start
4:30 operating the computer only when the
4:32 operating system is fully loaded into
4:35 the computer's memory and it is fully
4:38 operational this process of loading the
4:40 operating system is called the booting
4:43 operation all right so far we have
4:46 discussed in detail the starting phase
4:48 of the computer called the booting
4:51 process let us now focus on how computer
4:54 perform the tasks that user wish to use
4:56 the computer a computer is a versatile
4:58 machine that can be used for many applications
5:00 applications
5:02 after the operating system is loaded the
5:05 computer becomes fully operational at
5:07 this stage the user can start
5:10 interacting with the computer the user
5:12 interact with the operating system and
5:14 internally the operating system interact
5:17 with the computer hardware let us
5:19 consider one example to understand the
5:21 computer operations when the user
5:24 executes the command to run a specific
5:26 software the operating system loads the
5:28 program into the main memory of the
5:31 computer the main memory of the computer
5:34 is called Random Access Memory
5:37 abbreviated as RAM in computer jargon it
5:40 is also referred as the primary memory
5:43 of the computer or temporary memory each
5:46 computer is also equipped with another
5:48 crucial piece of Hardware component
5:50 called a central processing unit
5:54 abbreviated as CPU the CPU is the brain
5:56 of the computer that provide the
5:59 processing power the main task of the
6:02 process is to execute the program that
6:04 provide the desired functionality to the
6:07 user the CPU is also called a micro
6:11 processor or simply a processor the
6:13 processor is the brain of the computer
6:15 that decodes the program instructions
6:18 and executes program instructions one by
6:21 one the processor starts program
6:23 execution by retrieving the program
6:25 instructions and the corresponding data
6:28 from the main memory of the computer the
6:30 processor competitively performs this
6:33 operation called instruction cycle
6:36 during the program execution in computer
6:39 jargon this CPU operation is called
6:43 Fetch decode execute cycle the processor
6:45 internally decodes each program
6:48 instruction one by one and operates on
6:51 the data as per the program instruction
6:54 during the program execution phase the
6:55 user can provide the input to the
6:58 computer with the help of input devices
7:02 such as keyboard and mouse the data
7:04 processing is one of the important
7:07 functions of the processor the CPU
7:09 operates on the data the result or the
7:12 processed data is sent back to the main
7:15 memory RAM the processed data is then
7:17 presented to the user with the help of
7:20 output devices such as a printer or
7:23 display monitor the processed data can
7:25 also be stored into the permanent memory
7:28 of the computer called the secondary
7:31 memory or a dis memory the modern
7:33 processor can work at lightning speed
7:36 the processor can easily execute
7:38 multiple programs simultaneously this
7:41 function is called Process Management
7:43 and it is managed by the operating
7:45 system when the user commands the
7:48 computer to shut down the operating
7:50 system terminates all the processes
7:53 currently running on the system and the
7:55 data is stored into the permanent memory
7:58 of the computer for future use the user
8:00 at this stage can safe turn off the
8:03 power supply so that brings us to the
8:06 end of this tutorial on how computer
8:09 works please visit our website learn
8:11 computerscience online.com to learn
8:13 computer science
8:15 fundamentals if you have liked this
8:17 video then please give us a thumbs up
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8:22 thanks for watching and I will see you
8:24 soon with another computer science tutorial
