Commenting in Popular Programming Languages

Every main programming language implements comments. Comments are ignored by the compiler and this is how a script generates it's own documentation. We know that Good code is self-documenting. We comment once we delete a chunk of code or to prevent rethink. If we build a library or framework, some sort of API documentation is very important to other developers for easy grasping. Remember to comment as often as possible. It’s important! Here is the list of comment styles of various languages_ 

Ada

-- Comment in Ada
            

ActionScript

// Single line comment in Action Script
            

/* Multi-line comment
                in ActionScript */
            

Apple Script

-- Single line comment in Apple Script
            

(* Multi-line comment
                in ActionScript *)
           

Assembly

# Comment in Assembly Language 
            

Basic

REM Comment in Basic
            

Bash Script

# Comment in Bash Script
            

C#

// Comment in C#
            

/* Multi-line comment
                in C# */
           

C

/* Comment in C. This comment syntax is guaranteed to work on every compiler */

// Comment in C. but it might present portability challenges
            

Clojure

; Comment in Clojure
            

Cobol

* Comment in Cobol
            

CoffeScript

# Comment in CoffeScript
            

ColdFusion

<!--- Comment in ColdFusion --->
            

CSS

/* Comment in CSS */
            

Curl

| Single Line Comment in Curl
            

|# Multi-line comment 
                in Curl #|
           

D

// Comment in D
            

/+ Multi-line comment
                in D +/
           

Delphi

// Single line comment in Delphi 
            

{ Multi-line comment
                in Delphi }
           

Elixir

% Comment in Elixir
            

Erlang

% Comment in Erlang
            

Fortran

! Comment in Fortran
            

Go

// Single line comment in Go
            

/* Multi-line comment
                in Go */
           

Haskell

-- Single line comment in Haskell
            

{- Multi-line comment
                in Haskell -}
           

HTML

<!-- Comment in HTML-->
            

Java

// Single line comment in Java
            

/* Multi-line comment
                in Java */
        

     /** Multi-line documentation comment
            in Java */
       

Javascript

// Comment in Javascript
            

/* Multi-line comment
                in JavaScript */

           

Kotlin

// Comment in Kotlin
            

/* Multi-line comment
                in Kotlin */
           

LAN

<!-- Comment in Lan -->
            

LaTex

% Comment in LaTex
            

Lua

-- Single line comment in Lua
            

--[[Multi line comment 
                in Lua--]]
           

Matlab

% Comment in Matlab
            

%{ Multi line comment 
                in Matlab %}
           

Objective C

// Comment in Objective C
            

/* Multi-line comment
                in Objective C */
           

Pascal

{ Single line comment in Pascal }
            

{* Multi-line comment
                in Pascal *}
           

Perl

# Comment in Perl
            

PHP

// Comment in PHP
            

PowerShell

# Single line comment in PowerShell
            

<# Multi-line comment
                in PowerShell #>
           

Python

# Comment in Python
            

""" Multi line comment 
                in Python """
           

R

# Single line comment in R
            

<# Multi-line comment
                in R #>
           

Ruby

# Comment in Ruby
            

Rust

// Single line comment in Rust 
            

/* Multi-line comment
                in Rust */
           

S-Lang

% Comment in S-Lang
            

Scala

// Single Line Comment in Scala
            

/* Multi line comment 
                in Scala */
           

SPARK

-- Comment in SPARK
            

SQL

-- Comment in SQL
            

Swift

// Comment in Swift
            

/* Multi line comment 
                in Swift */
           

TCL

# Single line comment in TCL
            

<# Multi-line comment
                in TCL #>
           

TSQL

-- Comment in TSQL
            

/* Multi-line comment
                in TSQL */
           

VB

' Comment in VB
            

XML

<!-- Comment in XML -->
            

LISP

; Single line comment in XML
            

#| Multi-line comment
                in LISP |#