linux-chmod-command

 https://opensource.com/article/19/8/linux-chmod-command

https://quickref.me/chmod

Permissions

Abbreviation	Permission	Value
r	Read	4
w	Write	2
x	Execute	1
-	No permission	0

Permission analysis of "dir"

d  rwx  r-x  r-x
┬  ─┬─  ─┬─  ─┬─  
│   │    │    │  
│   │    │    └─ 4. Other｜5 (4+0+1)
│   │    └────── 3. Group｜5 (4+0+1)
│   └─────────── 2. User ｜7 (4+2+1)
└─────────────── 1. File Type | directory

ile Types

Abbreviation	File Type
d	Directory
-	Regular file
l	Symbolic Link

Objects

Who (abbr.)	Meaning
u	User
g	Group
o	Others
a	All, same as ugo

\\