Comments in Shell Script Last Updated : 19 Apr, 2025 Comments Improve Suggest changes Like Article Like Report Comments are the useful information that the developers provide to make the reader understand the source code. It explains the logic or a part of it used in the code. Comments are usually helpful to someone maintaining or enhancing your code when you are no longer around to answer questions about it. These are often cited as a useful programming convention that do not take part in the output of the program but improve the readability of the whole program.Types of Comments in Shell ScriptingThere are two types of comments:Single-line commentsMulti-line comments1. Single-line commentsA single-line comment starts with a hashtag symbol with no white spaces (#) and lasts till the end of the line. If the comment exceeds one line then put a hashtag on the next line and continue the comment.The shell script is commented out prefixing # character for single-line comment. Single-line comments are useful for brief explanations of code snippets or specific lines.Syntax:# This is a commentExample:# Single line commentecho "hello world"Output:In this example, the comment explains the purpose of the script, and it is not executed by the shell.2. Multi-line commentsMulti-line comment is a piece of text enclosed in a delimiter ('') on each end of the comment. Again there should be no white space between delimiter (' '). They are useful when the comment text does not fit into one line; therefore need to span across lines. Multi-line comments or paragraphs serve as documentation for others reading your code. See the following code snippet demonstrating multi-line comment.Syntax:: 'This is aMulti-line comments'Example:echo "multiline comments": ' This section explains the upcoming code block'Output:The multi-line comment section is ignored by the shell, making it a perfect place to add detailed explanations or documentation.ConclusionComments are an invaluable part of writing clear, maintainable shell scripts. They help explain the code's logic and intent, making it easier for others (or yourself) to understand and maintain in the future. Using single-line comments for brief notes and multi-line comments for more detailed explanations can make your scripts more readable and professional. Comment More infoAdvertise with us Next Article Comments in Shell Script P priyampatel9911 Follow Improve Article Tags : Linux-Unix Shell Script Similar Reads Introduction to Linux Shell and Shell Scripting If we are using any major operating system, we are indirectly interacting with the shell. 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