File Permissions

# View permissions
ls -la

# Output looks like:
# -rw-r--r--  1 fabiocorrea  staff  1234 Jan  1 12:00 file.txt
# drwxr-xr-x  5 fabiocorrea  staff   160 Jan  1 12:00 folder/

Symbol	Meaning
r	Read
w	Write
x	Execute
d	Directory
-	Not set

Changing Permissions

# Make a script executable
chmod +x script.sh

# Make a file read-only
chmod 444 file.txt