Engineering Full Stack Apps with Java and JavaScript
A programmer create software through a process called programming or coding. The purpose of programming is to develop an executable computer program that will automate performing a specific task or solving a given problem.
Programming involves activities such as analysis, design, generating algorithms and implementation of algorithms in a target programming language. These activities are also called as Software Development Lyfecycle (SDLC).
Programming languages are used to write programs. Programming languages like C, C++, Java, Fortran, JavaScript, Lisp, Python, Ruby, Smalltalk, etc. are similar to your communication languages like English, German, French etc. While you use the communication languages to talk to different people, you use programming languages to tell computers what to do.
A computer platoform might understand certain language, and is usually called a low level programming language. A low-level programming language is a programming language that provides little or no abstraction from a computer's instruction set architecture; commands or functions in the language map closely to processor instructions.
However, it might not be that easy to learn and understand such a language. Therefore, there are high level languages closer to your speaking language like English. There will be other software, like compilers or interpreters, that can convert a high level language to a low level machine language before executing them.
A compiler is a computer program that transforms source code written in a programming language into another computer language, often in a binary form, that is understood by the computer platform or operating system.
An interpreter is a computer program that directly executes instructions written in a programming or scripting language, without previously compiling them into a paltform specific code
Compiled languages uses a compiler to translate the source code to platform/operating system specific form and then this compiled form is taken to all computers running using that platform/operating system. Interpreted languages generally compile line-by-line and execute them.
Newer programming languages like Java, Python etc. uses a combination of compiler and interpreter; a compiler may output some form of intermediate bytecode (Java's .class files or Python's .pyc files), which is then executed by a bytecode interpreter (Java Virtual Machine or Python virtual machine).