5 Misunderstood Linux Commands: Explained

Linux users, whether seasoned administrators or curious beginners, often stumble over some of the most fundamental commands.

These errors can lead to anything from minor headaches to catastrophic data loss.

But fear not — these pitfalls are easy to avoid with a bit of knowledge.

Here are five of the most common Linux command mistakes and how to fix them.

5 Misunderstood Linux Commands: Explained

Ready to become a Linux master in 2025?

Let’s dive into five often misunderstood Linux commands to help you work smarter, faster, and more effectively.

Misunderstanding File Permissions with chmod

The chmod command is indispensable for setting file permissions.

But the octal permission system it uses — like 755 or 700 —is frequently misunderstood.

A common mistake is not knowing what these numbers mean. They represent the access rights for the file owner, group members, and others.

For example, 700 gives the file owner full control while locking everyone else out, whereas 755 allows others to execute and read but not modify.

The Fix: Learn the basics of the octal system. It’s straightforward once you understand that each digit corresponds to read, write, and execute permissions for different user groups.

Confusing kill and killall

When a program freezes, many users turn to kill to terminate the offending process. The problem arises when they use killall instead, thinking it’s just a shortcut. It isn’t.

kill targets a specific process by its ID (PID), making it precise. On the other hand, killall terminates all processes with the same name — a nuclear option that could bring down critical systems if misused.

The Fix: Double-check which command you’re using. If you only need to stop one instance, stick with kill. Reserve killall for scenarios where you’re sure no vital processes will be affected.

Reckless Use of dd

The dd command is sometimes jokingly called the "disk destroyer" for a reason. This powerful tool is often used to copy data at the byte level or create bootable drives, but one small typo in its input or output parameters can erase an entire disk.

The Fix: Always triple-check the syntax before pressing Enter. Better yet, practice in a sandbox environment or with non-critical data until you’re confident in its use.

Underutilizing find

Most users know find as a tool for locating files. But many fail to realize its real power: it can perform actions on the files it discovers, such as deleting old logs or organizing directories.

For instance, you could use find to identify all log files older than seven days and delete them automatically.

The mistake here is stopping at its basic functionality and not leveraging its full potential.

The Fix: Explore find for its advanced features, like the ability to execute commands on located files. With a bit of effort, it can become a versatile assistant for cleaning and organizing your file system.

Thinking tar Is Just for Compression

Many users treat tar as a tool exclusively for compressing files. In reality, its primary purpose is archiving—compression is an optional extra.

For large backups, skipping compression can save time and reduce system load. Ignoring this distinction often leads to unnecessarily complex or inefficient workflows.

The Fix: Remember that tar is first an archiver. Consider your needs before adding compression, and don’t overlook its value for tasks like bundling files without compressing them.

If you're eager to improve your Linux skills even more, check out the rest of our Linux Mastery articles tutorials, including:

- 10 Crucial Linux Commands for Troubleshooting

- The 10 Most Dangerous Linux Commands

Wrapping Up

Linux is a powerful and versatile operating system, but its commands require precision and understanding.

Small mistakes — like misinterpreting permissions, misusing a command, or underestimating a tool’s capabilities — can have outsized consequences.

Fortunately, these pitfalls are easy to fix with a little knowledge and practice.

The next time you’re typing away in the terminal, take a moment to double-check your commands. It’s a small step that could save you a world of trouble.