The difference between reading and execution, file resolution

Question

This may sound like a fairly simple question, but I'm a little puzzled by what the “reading” of the file and the “execution” of the file are.

For example: User 1 buys a ticket from the website and wants to view the ticket (like jpeg) that is displayed on the website.

Is this a "read" folder? or is it actually running a folder?

If the user rights are set to read-only, this means that the user MAY access the file through an action on the website (in this case, the image of the ticket purchased), but cannot access the file using the direct URL link right? For example, www.exampletickets.com/user1/tickets

Answer 1

Folders:

Execute -> Actually enter that folder but not be 
able to read it contents, see what files are located there. 

Read -> Be Able To Read Folder Contents

Write -> Edit folders data. delete or create new files/folders inside it and etc

File Permissions:

Execute -> if it script like index.php run it to get data from it

Read -> if it text file like index.html or index.php be able to read it

Write -> ability to change its data

As for security, these permissions are only a problem when your server is accessible to other users (not from your team), and this mainly happens when people using hosting services do not get a dedicated operating system, but there is one operating system and all users where they upload their data. Therefore, if they were not properly protected, they could view and edit each other's source codes.

Today, as usual, you get a dedicated server, with a large number of security tools and an operating system available only to you and to no one else (virtualization).

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Answer 2

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( ?) → https://serverfault.com/questions/345833/what-are-perfect-unix-permissions-for-usual-web-project-directories