docs(CMD): explain what a .cmd file is with examples

What
- Documented `.cmd` files as Windows command scripts similar to `.bat`.
- Key features:
  - Plain text files with `.cmd` extension.
  - Executed by Windows Command Prompt (cmd.exe).
  - Run commands sequentially, automating common tasks.
  - Introduced with Windows NT; more modern alternative to legacy `.bat` files.
- Included examples:
  1. Hello World:
     ```
     @echo off
     echo Hello, World from CMD!
     pause
     ```
  2. Open IntelliJ IDEA with a Java file:
     ```
     @echo off
     start "" "C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2023.3\bin\idea64.exe" "D:\Projects\JavaTutorials\src\Main.java"
     ```

Why
- Provides a foundation for understanding automation on Windows systems.
- Shows how `.cmd` scripts simplify repetitive tasks like launching programs or running sequences of commands.
- Distinguishes `.cmd` from older `.bat` while showing near-identical syntax.

How
- `@echo off`: prevents commands from being displayed while executing.
- `echo`: prints messages to console.
- `pause`: waits for user input before closing the window.
- `start ""`: launches a program in a new Command Prompt window.
- Paths provided after `start` point to executable and optional file arguments.

Logic
- Inputs: sequence of command-line instructions inside `.cmd`.
- Outputs: automated execution of those commands in Windows Command Prompt.
- Flow:
  1. Save commands into `.cmd` file.
  2. Double-click or run file in CMD.
  3. CMD executes instructions line by line.
- Edge cases:
  - Quoting required for paths with spaces.
  - Missing quotes or wrong paths lead to "file not found" errors.
- Complexity / performance: trivial; execution speed depends on underlying commands.
- Concurrency / thread-safety: multiple `.cmd` files can run in separate CMD instances.

Real-life applications
- Automating software builds or environment setup.
- Launching development tools with specific project files.
- Creating shortcuts for repetitive administrative tasks.
- Batch file replacements in modern Windows scripting workflows.

Notes
- `.cmd` and `.bat` are nearly interchangeable; `.cmd` was introduced for NT-based Windows (NT/2000/XP and later).
- For advanced scripting, Windows PowerShell (`.ps1`) offers richer features, but `.cmd` remains widely used for legacy support and simple automation.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>

Author: Someshdiwan

Tips And Tricks/What is a .cmd File.txt

@@ -0,0 +1,24 @@
+What is a .cmd File?
+
+A .cmd file is very similar to a .bat file.
+It is used in Windows to automate tasks in the Command Prompt.
+
+Key Features of a .cmd File:
+- Text file with .cmd extension.
+- Runs sequential commands in CMD.
+- Almost identical to .bat, but introduced in Windows NT.
+- Preferred when using modern Windows scripting over legacy .bat.
+
+Example 1: Simple Hello World
+@echo off
+echo Hello, World from CMD!
+pause
+
+Example 2: Open IntelliJ IDEA
+@echo off
+start "" "C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2023.3\bin\idea64.exe" "D:\Projects\JavaTutorials\src\Main.java"
+
+How It Works:
+- start "" launches a program in a new window.
+- First path → IntelliJ executable.
+- Second path → Java file to open.