Script Vs Program Vs Software Vs Applications

 SCRIPT

A computer script is a list of commands that are executed by a certain program or scripting engine. 

For example all batch files ( .bat) files in Windows is a script written in DOS commands. 

Scripts may be used to automate processes on a local computer (batch files)  or to generate Web pages on the Web (web server). 

For example, DOS scripts (batch files) and VB Scripts may be used to run processes on Windows machines, while AppleScript scripts can automate tasks on Macintosh computers. 

ASP, JSP, and PHP scripts are often run on Web servers to generate dynamic Web page content.

Script files are usually just text documents that contain instructions written in a certain scripting language. 

This means most scripts can be opened and edited using a basic text editor. However, when opened by the appropriate scripting engine, the commands within the script are executed. 

VB (Visual Basic) scripts, for example, will run when double-clicked, using Windows' built-in VB scripting support. 

Since VB scripts can access and modify local files, you should never run a VB script that you receive as an unknown e-mail attachment.

WEB SERVER

A web server is a computer that runs websites.

It's a computer program that distributes web pages as they are requisitioned.

The basic objective of the web server is to store, process and deliver web pages to the users.

This intercommunication is done using Hypertext Transfer Protocol (HTTP). 

These web pages are mostly static content that includes HTML documents, images, style sheets, test etc. 

Apart from HTTP, a web server also supports SMTP (Simple Mail transfer Protocol) and FTP (File Transfer Protocol) protocol for emailing and for file transfer and storage.

The main job of a web server is to display the website content. 

If a web server is not exposed to the public and is used internally, then it is called Intranet Server. 

When anyone requests for a website by adding the URL or web address on a web browser’s (like Chrome or Firefox) address bar (like www.economictimes.com), the browser sends a request to the Internet for viewing the corresponding web page for that address. 

A Domain Name Server (DNS) converts this URL to an IP Address (For example 192.168.216.345), which in turn points to a Web Server.

PROGRAM

Program is a common computer term that can be used as both a noun and a verb. 

A program (noun) is executable software that runs on a computer. 

It is similar to a script, but is often much larger in size and does not require a scripting engine to run. 

Instead, a program consists of compiled code that can run directly from the computer's operating system.

These programs are often called applications, which can be used synonymously with "software programs." 

On Windows, programs typically have an .EXE file extension, while Macintosh programs have an .APP extension.

When "program" is used as verb, it means to create a software program. 

For example, programmers create programs by writing code that instructs the computer what to do. 

The functions and commands written by the programmer are collectively referred to as source code. 

When the code is finished, the source code file or files are compiled into an executable program.

When programmers create software programs, they first write the program in source code, which is written in a specific programming language, such as C or Java. 

These source code files are saved in a text-based, human-readable format, which can be opened and edited by programmers. 

However, the source code cannot be run directly by the computer. In order for the code to be recognized by the computer's CPU, it must be converted from source code (a high-level language) into machine code (a low-level language). This process is referred to as "compiling" the code.

SOFTWARE

Computer software is a general term that describes computer programs.

Related terms such as software programs, applications, scripts, and instruction sets all fall under the category of computer software. Therefore, installing new programs or applications on your computer is synonymous with installing new software on your computer.

Source: Techterms