File Creation & Permissions on Linux (Beginner Level)

Before working with file contents, we first need to know how to create a file in Linux.

Let’s start by creating a simple file using a safe, beginner-friendly command.

1️⃣ Creating a file

touch hello.txt

What it does:

• Creates an empty file

• If the file already exists, updates its timestamp

• Does not add content

This is the safest way to create a file.

2️⃣ Verifying a file exists

ls -l hello.txt

Example output:

-rw-r--r--. 1 ec2-user ec2-user 0 Jan 22 04:05 hello.txt

This single line tells you everything important about the file.

3️⃣ Understanding file ownership (the two ec2-users)

Every file in Linux has two owners:

Field	Meaning
Owner (user)	The user who owns the file
Group	The group that owns the file

Owner: ec2-user
Group: ec2-user

4️⃣ Understanding permissions (-rw-r--r--)

Permissions are always checked in this order:

1 Owner

2 Group

3 Others

Breakdown:

-rw- r-- r--
│    │    └─ Others: read only
│    └─ Group: read only
└─ Owner: read & write

Meaning:

• You (owner) can read and write the file

• Group members can only read

• Everyone else can only read

5️⃣ File type indicator

The first character shows the type:

Symbol	Meaning
-	Regular file
d	Directory

🎯 Key mental model (remember this)

Linux files always have:

• An owner

• A group

• Permissions for owner, group, and others

This model applies to every file and directory on Linux.