- Operating System.
- File and File System.
Operating System
There are many operating systems nowadays. The most popular ones are Microsoft Windows, macOS, and Linux.
An operating system is system software that manages computer hardware, software resources, and provides common services for computer programs.
I’m sure you are familiar with Windows and macOS. However, you might not familiar with Linux much. Linux is the leading operating system on the servers. Android is powered by the Linux operating system as well.
In simple words, we can say that the operating system manages hardware. The main components of any computer are CPU, RAM memory, and hard driver. They will not work by themselves. They need some system to manage them and Operating System is software that manages hardware. Also, we can install different programs on top of the operating system. For example, the browser, games on your pc, etc.
File and File System
In the previous article, we said we can imagine computer memory as a big canvas. Now, somehow we need to manage this one big piece of data. The way we manage is by dividing them into files and organizing all the files as a file system.
There are two types of files. The first one is a directory(folder). The directory can have other files inside. Remember we can refer to directories as files as well. The second type is an actual file. It has a great number of formats(.txt, pdf, png). In fact, you even can create your own format.
Every file has a header, body, and ending point of the file. The header mainly contains metadata(data about data) about a file. Things like the file format, how to read the file, size, who created it, etc. The body will contain the actual content of the file. The ending part indicates that there is no more content of the file.
Each file has a specific path in the file system. A file path specifies a unique location in a file system.
For example, my notes.txt file on my Desktop will have this file path.
File path: C:\Users\Beknazar\Desktop\notes.txt
The File System is the way we organize files. It is based on a tree data structure. It has a root directory(C: for Windows and / for macOS)
Please take my Java Course for video lectures.This article is part of the series of articles to learn Java programming language from Tech Lead Academy:Introduction to programming
OS, File, and File System
Working with terminal
Welcome to Java Programming Language
Variables and Primitives in Java
Convert String to numeric data type
Input from the terminal in Java
Methods with Java
Java Math Operators and special operators
Conditional branching in Java
Switch statement in Java
Ternary operator in Java
Enum in Java
String class and its methods in Java
Loops in Java
Access modifiers in Java
Static keyword in Java
The final keyword in Java
Class and Object in Java
Object-Oriented Programming in Java
OOP: Encapsulation in Java
OOP: Inheritance in Java
OOP: Abstraction in Java
OOP: Polymorphism in Java
The method Overriding vs Overloading in Java
Array in Java
Data Structures with Java
Collection framework in Java
ArrayList in Java
Set in Java
Map in Java
Date and Time in Java
Exception in Java
How to work with files in Java
Design Patterns
Generics in Java
Multithreading in java
Annotations in Java
Reflection in Java
Reflection & Annotations - The Powerful Combination
Run terminal commands from Java
Lambda in Java
Unit Testing in Java
Big O Notation for coding interviews
Top Java coding interview questions for SDET