World of Programming Languages

 In 1992, Andrew S. Tanenbaum, recognized computer scientist and author of the Minix microkernel system, wrote a Usenet article on the newsgroup comp.os.minix with the title "Linux is obsolete",[38] which marked the beginning of a famous debate about the structure of the then-recent Linux kernel. Among the most significant criticisms were that: The kernel was monolithic and thus old-fashioned. The lack of portability, due to the use of exclusive features of the Intel 386 processor. "Writing a new operating system that is closely tied to any particular piece of hardware, especially a weird one like the Intel line, is basically wrong."[39] There was no strict control of the source code by any individual person.[40] Linux employed a set of features which were useless (Tanenbaum believed that multithreaded file systems were simply a "performance hack").[41] Tanenbaum's prediction that Linux would become outdated within a few years and replaced by GNU Hurd ...

 Linux was originally developed for personal computers based on the Intel x86 architecture, but has since been ported to more platforms than any other operating system.Because of the dominance of the Linux-based Android on smartphones, Linux also has the largest installed base of all general-purpose operating systems.Although it is used by only around 2.3 percent of desktop computers,[26][27] the Chromebook, which runs the Linux kernel-based Chrome OS, dominates the US K–12 education market and represents nearly 20 percent of sub-$300 notebook sales in the US. Linux is the leading operating system on servers (over 96.4% of the top 1 million web servers' operating systems are Linux), leads other big iron systems such as mainframe computers, and is the only OS used on TOP500 supercomputers (since November 2017, having gradually eliminated all competitors). Linux also runs on embedded systems, i.e. devices whose operating system is typically built into the firmware and is highly tailo...

 JavaScript is the world's most popular programming language. JavaScript is the programming language of the Web. JavaScript is easy to learn. This tutorial will teach you JavaScript from basic to advanced. Use the Menu We recommend reading this tutorial, in the sequence listed in the menu. If you have a large screen, the menu will always be present on the left. If you have a small screen, open the menu by clicking the top menu sign ☰.

  The   Java Class Library   is the   standard library , developed to support application development in Java. It is controlled by   Oracle   in cooperation with others through the   Java Community Process   program. [70]   Companies or individuals participating in this process can influence the design and development of the APIs. This process has been a subject of controversy during the 2010s. [71]   The class library contains features such as: The core libraries, which include: IO/ NIO Networking  (NOTE: new  HTTP Client  since Java 11) Reflection Concurrency Generics Scripting/Compiler Functional programming  (Lambda, Streaming) Collection libraries  that implement  data structures  such as  lists ,  dictionaries ,  trees ,  sets ,  queues  and  double-ended queue , or  stacks [72] XML  Processing (Parsing, Transforming, Validating) libraries Security [73]...

 The Java Development Kit (JDK) is an implementation of either one of the Java Platform, Standard Edition, Java Platform, Enterprise Edition, or Java Platform, Micro Edition platforms[1] released by Oracle Corporation in the form of a binary product aimed at Java developers on Solaris, Linux, macOS or Windows. The JDK includes a private JVM and a few other resources to finish the development of a Java application.[2] Since the introduction of the Java platform, it has been by far the most widely used Software Development Kit (SDK).[citation needed] Java Development Kit Developer(s) Oracle Corporation Stable release 17.0.0 / 14 September 2021; 16 days ago Operating system Windows NT, macOS (x64), Linux, Solaris Platform IA-32, x64, ARM, SPARC Type Software development kit License Sun License (most of it also under GPL) Website www.oracle.com/technetwork/java/ The JDK is available for 64-bit x64 macOS (and that version also works with Rosetta 2), while an early access build (develope...

  The traditional   Hello world program   can be written in Java as: [57] public class HelloWorldApp { public static void main ( String [] args ) { System . out . println ( "Hello World!" ); // Prints the string to the console. } } All source files must be named after the public class they contain, appending the suffix  .java , for example,  HelloWorldApp.java . It must first be compiled into bytecode, using a  Java compiler , producing a file with the  .class  suffix ( HelloWorldApp.class , in this case). Only then can it be executed or launched. The Java source file may only contain one public class, but it can contain multiple classes with a non-public access modifier and any number of public  inner classes . When the source file contains multiple classes, it is necessary to make one class (introduced by the  class  keyword) public (preceded by the  public  keyword) and name the source file...

  Java uses an   automatic garbage collector   to manage memory in the   object lifecycle . The programmer determines when objects are created, and the Java runtime is responsible for recovering the memory once objects are no longer in use. Once no references to an object remain, the   unreachable memory   becomes eligible to be freed automatically by the garbage collector. Something similar to a   memory leak   may still occur if a programmer's code holds a reference to an object that is no longer needed, typically when objects that are no longer needed are stored in containers that are still in use. If methods for a non-existent object are called, a   null pointer   exception is thrown. [52] [53] One of the ideas behind Java's automatic memory management model is that programmers can be spared the burden of having to perform manual memory management. In some languages, memory for the creation of objects is implicitly allocated on the...