Computer science 101: Hardware vs software components

Hardware vs. Software#

Software describes a collection of programs and procedures that perform tasks on a computer. Software is an ordered sequence of instructions that change the state of a computer’s hardware.There are three general types of software:

• System software
• Programming software
• Application software

When you think of computer science, software is probably what comes to mind. Software is what developers actually code. Those programs are then installed onto a hard drive.

Hardware is anything physically connected to a computer. For example, your display monitor, printer, mouse, and hard drive are all hardware components.

Hardware and software interact with each other. The software “tells” the hardware which tasks to perform, and hardware makes it possible to actually perform them.

Note: Most computers require at least a hard drive, display, keyboard, memory, motherboard, processor, power supply, and video card to function.

Hardware components#

Now that we understand the difference between hardware and software, let’s learn about the hardware components of a computer system. Remember: hardware includes the physical parts of a computer that the software instructs.

CPU#

The Central Processing Unit (CPU) is a physical object that processes information on a computer. It takes data from the main memory, processes it, and returns the modified data into the main memory. It is comprised of two sub-units:

• The control unit (CU): controls data flow from and into the main memory
• The arithmetic and logic unit (ALU): processes the data

Von Neumann architecture#

This computer architecture design, created by John von Neumann in 1945, is still used in most computers produced today. The Von Neumann architecture is based on the concept of a stored-program computer. Instruction and program data are stored in the same memory.

This architecture includes the following components:

• Control Unit
• Inputs/Outputs
• Arithmetic and Logic Unit (ALU)
• Memory Unit
• Registers

Software components#

Now let’s discuss the different software components that we need to have a functioning computer. Remember: software comprises the set of programs, procedures, and routines associated needed to operate a computer.

Machine language#

A computer can only process binary: a stream of ones and zeros. Binary is the computer’s language. Instructions for the computer are also stored as ones and zeros that the computer must decode and execute.

Assembly language#

Assembly language is a human-readable instruction mode that translates binary opcode into assembly instruction. A CPU cannot process or execute assembly instructions, so an encoder is required that can convert assembly language to machine language.

Assembler#

An assembler translates an assembly language program into machine language. The code snippet below is an assembly program that prints “Hello, world!” on the screen for the X86 processor.

section	.data
   text db 'Hello, world!'

section	.text
   global _start              
	
_start:
   mov	rax, 1               
   mov	rdi, 1
   mov	rsi, text
   mov	rdx, 14
   syscall
	
   mov	rax, 60
   mov   rdi, 0
   syscall

High-level languages#

Assembly language is referred to as a low-level language because it’s a lot like machine language. To overcome these shortcomings, high-level languages were created.

These are called programming languages, and they allow us to create powerful, complex, human-readable programs without large numbers of low-level instructions. Some of the most famous high-level languages are:

• Python
• C++
• Java

How do you design software?#

Software design is the process of transforming particular requirements into a suitable program using code and a high-level language. We need to properly design a program and system that meets our goals.

Developers use software design to think through all the parts of their code and system. Software design includes three levels:

• Architectural Design: an abstract version of the program or system that outlines how components interact with each other.
• High-level Design: this part breaks the design into sub-systems and modules. High-level design focuses on how the system should be implemented.
• Detailed Design: this part deals with the implementation. This is here we define the logical structure of each module.

What to learn next#

Congrats! You should now have a solid idea of hardware, software, and the components of a computer. These are essential to your foundation as a computer scientist. For your next step on this journey, you should learn about:

• Binary conversions
• Data representation
• Data compression
• Basic syntax of programming language

Now that you know these basics, you can advance to start learning your first programming language with one of our courses:

• Learn to Code: Python for Absolute Beginners
• Learn to Code: C++ for Absolute Beginners
• Learn to Code: C# for Absolute Beginners
• Learn to Code: Java for Absolute Beginners
• Learn to Code: JavaScript for Absolute Beginners
• Learn to Code: Ruby for Absolute Beginners

Happy learning!

Continue reading about computer science#

• Computer Number Systems 101: Binary & Hexadecimal Conversions
• Learn How to Code: the beginner’s guide to coding and syntax
• Absolute beginner’s guide to computers and programming