▶️ 3. Mini computers
💎 have relatively lower speed, can handle multi-users, are smaller in size than the mainframe computers.
💎They use terminals for inputs and output.
💎Mini computers are used in small organizations.
▶️ 4. Microcomputers
💎 Are the most widely used type of computers.
💎They are single users, can
fit on desktops, are of varying capacity and easy to handle. Microcomputers are sometimes referred as personal computers.
💎They have video display unit for output purpose.
💎Data is entered through the keyboard and by the help of floppy disk.
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💎 have relatively lower speed, can handle multi-users, are smaller in size than the mainframe computers.
💎They use terminals for inputs and output.
💎Mini computers are used in small organizations.
▶️ 4. Microcomputers
💎 Are the most widely used type of computers.
💎They are single users, can
fit on desktops, are of varying capacity and easy to handle. Microcomputers are sometimes referred as personal computers.
💎They have video display unit for output purpose.
💎Data is entered through the keyboard and by the help of floppy disk.
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Computers Systems
💎System is a group of components, consisting of subsystems or procedures that work in a coordination fashion to achieve some objective.
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💎System is a group of components, consisting of subsystems or procedures that work in a coordination fashion to achieve some objective.
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Hardware
💎 Is the physical equipment of the computer
you see, you use to and the parts you can touch.
💎Basic Physical components of a computer system.
💎The basic units of a computer system include
📌Central Processing Unit
(CPU),
📌Storage Devices,
📌Input Devices,
📌Output Devices
📌and Communication Bus.
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💎 Is the physical equipment of the computer
you see, you use to and the parts you can touch.
💎Basic Physical components of a computer system.
💎The basic units of a computer system include
📌Central Processing Unit
(CPU),
📌Storage Devices,
📌Input Devices,
📌Output Devices
📌and Communication Bus.
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1⃣Central Processing Unit (CPU) or Processor
📌 Brain of the system
📌 Depending on the instructions
of input devices it performs
operations on the data.
📌 It also controls the flow of data through the
system, directing the data to enter the system, placing it in memory and retrieving it when
required and directing the output.
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📌 Brain of the system
📌 Depending on the instructions
of input devices it performs
operations on the data.
📌 It also controls the flow of data through the
system, directing the data to enter the system, placing it in memory and retrieving it when
required and directing the output.
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💎 The CPU consists of Arithmetical Logic Unit and Control Unit
▶️ ALU (Arithmetical Logic Unit):
It takes logical decision and performs all type of arithmetical calculations.
▶️ CU (Control unit):
📌It controls all the activities of other units of computer system.
📌 It receives instructions from memory unit.
📌 It decodes these instructions.
📌 It decides the routing and storage of these instructions.
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▶️ ALU (Arithmetical Logic Unit):
It takes logical decision and performs all type of arithmetical calculations.
▶️ CU (Control unit):
📌It controls all the activities of other units of computer system.
📌 It receives instructions from memory unit.
📌 It decodes these instructions.
📌 It decides the routing and storage of these instructions.
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2⃣Primary Storage Devices / Main Memory
▶️ RAM (Random Access Memory)
📌 directly accessible by the CU and ALU
📌 Usually referred as Random Access Memory (RAM) because each memory location can be accessed without having to work sequentially through hundreds or even
thousands of memory locations called addresses;
📌 Holds instructions and data elements which are currently being used by the computer.
📌 The data Will be lost when the power is off;
▶️ ROM (Read Only Memory)
📌 This type of memory is integrated into the circuitry of the computer and cannot be altered without altering the computer circuitry.
📌 Used to store basic hardware information.
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▶️ RAM (Random Access Memory)
📌 directly accessible by the CU and ALU
📌 Usually referred as Random Access Memory (RAM) because each memory location can be accessed without having to work sequentially through hundreds or even
thousands of memory locations called addresses;
📌 Holds instructions and data elements which are currently being used by the computer.
📌 The data Will be lost when the power is off;
▶️ ROM (Read Only Memory)
📌 This type of memory is integrated into the circuitry of the computer and cannot be altered without altering the computer circuitry.
📌 Used to store basic hardware information.
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3⃣Secondary Storage Devices/ Auxiliary Memory
Secondary storage can take many forms, which have traditionally included
📌punched cards
📌papers tape
📌magnetic tape
📌magnetic disk
📎HDD (hard disk drive)
📌and magnetic drum.
This storage media are stores data and information permanently.
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Secondary storage can take many forms, which have traditionally included
📌punched cards
📌papers tape
📌magnetic tape
📌magnetic disk
📎HDD (hard disk drive)
📌and magnetic drum.
This storage media are stores data and information permanently.
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Hard Disk Drive(HDD)
💎 is part of a computer system which reads from and writes data on a disk which in turn becomes a file.
📌 A high capacity magnetic disk made up of metal which can be fixed in the system unit of the computer.
📌 Serves as a secondary storage.
📌 The amount of time it takes to retrieve (or store) data from (or to) disk is called the disk access time.
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💎 is part of a computer system which reads from and writes data on a disk which in turn becomes a file.
📌 A high capacity magnetic disk made up of metal which can be fixed in the system unit of the computer.
📌 Serves as a secondary storage.
📌 The amount of time it takes to retrieve (or store) data from (or to) disk is called the disk access time.
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4. Input/Output (IO) Devices
▶️ Input Devices
📌 Is the unit used to enter data into the computer so that it can be processed.
📌 It converts information from a form suitable to human beings to one understandable by the computer.
📌Keyboard
📌Mouse
📌Scanner and etc.
▶️ Output Devices
📌 Used to get data out of a computer so that it can be examined, analyzed or distributed to others.
📌 Convert the result of the only-machine understandable form to a form understandable by human beings.
📌The Visual Display Unit (VDU) or monitor or screen,
📌Printers and etc
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▶️ Input Devices
📌 Is the unit used to enter data into the computer so that it can be processed.
📌 It converts information from a form suitable to human beings to one understandable by the computer.
📌Keyboard
📌Mouse
📌Scanner and etc.
▶️ Output Devices
📌 Used to get data out of a computer so that it can be examined, analyzed or distributed to others.
📌 Convert the result of the only-machine understandable form to a form understandable by human beings.
📌The Visual Display Unit (VDU) or monitor or screen,
📌Printers and etc
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5. Communication Bus
💎 We have seen that there are different components of a computer and each performs a specific function.
💎 But to perform a given task in synchronized form there should be some mechanism of communication.
💎 For this reason, there is an electronic circuit which produces communication path between the different components of a computer system along which
data are transferred, that is Bus.
▶️ Internal Bus
which communicates the different parts of the CPU.
▶️ External Bus
which communicates the CPU with memory and peripheral devices.
💎 The size of the bus determines the speed of
efficiency of the computer.
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💎 We have seen that there are different components of a computer and each performs a specific function.
💎 But to perform a given task in synchronized form there should be some mechanism of communication.
💎 For this reason, there is an electronic circuit which produces communication path between the different components of a computer system along which
data are transferred, that is Bus.
▶️ Internal Bus
which communicates the different parts of the CPU.
▶️ External Bus
which communicates the CPU with memory and peripheral devices.
💎 The size of the bus determines the speed of
efficiency of the computer.
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Computer Software
📌 Software serves as an interface between a user and a computer.
📌 Hardware needs instructions in order to solve problem.
📌 The finite set of instructions (steps) that the computer follows to perform a given job is called a program.
📌 Any program to be executed first it should reside / loaded/ in the memory.
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📌 Software serves as an interface between a user and a computer.
📌 Hardware needs instructions in order to solve problem.
📌 The finite set of instructions (steps) that the computer follows to perform a given job is called a program.
📌 Any program to be executed first it should reside / loaded/ in the memory.
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Computer software is classified into two
1. System Software
2. Application Software
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1. System Software
2. Application Software
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1. System Software
Constitutes those programs which facilitates the work of the computer hardware.
💎 It organizes and manages the machine’s resources, handles the input/output devices.
💎 It controls the hardware by performing functions that users shouldn’t have to or are unable to handle.
💎 System programs make complex hardware more users friendly.
💎 It acts as intermediate between the user and the hardware.
💎 It enables the computer understand programming languages i.e. it serves as means of communication between user and a computer.
💎The important categories of system software are:
I. Operating system
II. Language software
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Constitutes those programs which facilitates the work of the computer hardware.
💎 It organizes and manages the machine’s resources, handles the input/output devices.
💎 It controls the hardware by performing functions that users shouldn’t have to or are unable to handle.
💎 System programs make complex hardware more users friendly.
💎 It acts as intermediate between the user and the hardware.
💎 It enables the computer understand programming languages i.e. it serves as means of communication between user and a computer.
💎The important categories of system software are:
I. Operating system
II. Language software
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Operating system (OS)
💎 Operating system coordinates the activity between the user and the computer.
💎 It serves as an intermediary between programs and hardwares.
Types of Operating Systems:
i. Single-user / Single tasking OS
📌 Only one program can be
run on a computer at a time.
📌 Also can serve only
one user at a time.
ii. Single-user / multi-tasking OS
📌 desktop and laptop computers now day
📌 popular OS's Like
💎Linux (Ubuntu)
💎Windows
💎macOS
iii. Multi-user
📌 Unix, VMS and mainframe operating systems, such as MVS (Multiple Virtual Storage).
iv. Real Time Operating System
📌 is capable of processing data so quickly that the results are available to influence the activity currently taking place.
📌 are used to control machinery, scientific instruments and industrial systems.
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💎 Operating system coordinates the activity between the user and the computer.
💎 It serves as an intermediary between programs and hardwares.
Types of Operating Systems:
i. Single-user / Single tasking OS
📌 Only one program can be
run on a computer at a time.
📌 Also can serve only
one user at a time.
ii. Single-user / multi-tasking OS
📌 desktop and laptop computers now day
📌 popular OS's Like
💎Linux (Ubuntu)
💎Windows
💎macOS
iii. Multi-user
📌 Unix, VMS and mainframe operating systems, such as MVS (Multiple Virtual Storage).
iv. Real Time Operating System
📌 is capable of processing data so quickly that the results are available to influence the activity currently taking place.
📌 are used to control machinery, scientific instruments and industrial systems.
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2. Language Software
💎Are software which are used by programmers to develop application software and translate programs to machine code.
💎Language software is a generic name consisting of various programs that serve as
📌 editors
📌 and translators to develop programs in a number of programming languages.
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💎Are software which are used by programmers to develop application software and translate programs to machine code.
💎Language software is a generic name consisting of various programs that serve as
📌 editors
📌 and translators to develop programs in a number of programming languages.
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Translator
💎 program that converts one or more languages to another language.
▶️ Three types of translators
I) Assemblers:
is a program that translates assembly languages into machine code.
II) Compiler:
is a program that translates a high level language into machine code.
>> creates an executable program.
📌 C++, JAVA, C# and e.t.c
III) Interpreter:
is a program that translates each instruction of high level language & executes the instruction before translating the next instruction.
📌 PHP, JAVASCRIPT, PYTHON and e.t.c
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💎 program that converts one or more languages to another language.
▶️ Three types of translators
I) Assemblers:
is a program that translates assembly languages into machine code.
II) Compiler:
is a program that translates a high level language into machine code.
>> creates an executable program.
📌 C++, JAVA, C# and e.t.c
III) Interpreter:
is a program that translates each instruction of high level language & executes the instruction before translating the next instruction.
📌 PHP, JAVASCRIPT, PYTHON and e.t.c
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▶️ High-level programming languages
Vs
▶️ Low-level programming languages
▶️ A High-level language
is a programming language designed to simplify computer programming.
💎 High-level source code contains easy-to-read syntax for human.
💎 Most common programming languages are considered
high-level languages.
C++, C#, Java, JavaScript, PHP, Python...
▶️ A Low-level language
💎 is a programming language that deals with a computer's hardware components and constraints.
💎 May also be referred to as a computer’s native language.
💎 Machine language and assembly language are popular examples of low-level languages.
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Vs
▶️ Low-level programming languages
▶️ A High-level language
is a programming language designed to simplify computer programming.
💎 High-level source code contains easy-to-read syntax for human.
💎 Most common programming languages are considered
high-level languages.
C++, C#, Java, JavaScript, PHP, Python...
▶️ A Low-level language
💎 is a programming language that deals with a computer's hardware components and constraints.
💎 May also be referred to as a computer’s native language.
💎 Machine language and assembly language are popular examples of low-level languages.
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▶️ Procedural
Vs ▶️ Object Oriented
Vs ▶️ Structured programming languages
▶️ A procedural programming language
💎consists of a set of procedure calls and a set of code for each procedure. Example: BASIC
▶️ A structural programming language emphasizes on separating a program’s data from its functionality. Example: C
▶️ Object oriented languages are based on entities known as objects. Example: Java
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Vs ▶️ Object Oriented
Vs ▶️ Structured programming languages
▶️ A procedural programming language
💎consists of a set of procedure calls and a set of code for each procedure. Example: BASIC
▶️ A structural programming language emphasizes on separating a program’s data from its functionality. Example: C
▶️ Object oriented languages are based on entities known as objects. Example: Java
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Application Software
📌 Is software that is designed to perform tasks for the specific area or areas by using more than one installation.
📌 Are usually called application packages as they may include a number of programs along with operating instruction, documentation and so forth.
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📌 Is software that is designed to perform tasks for the specific area or areas by using more than one installation.
📌 Are usually called application packages as they may include a number of programs along with operating instruction, documentation and so forth.
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