Importance of /temp and /trashdir folders content

Hello,

I am in the process of saving/downloading all my moodle files to my computer using FTP.

And I have two questions :

QUESTION 1 :

Is it necessary to retrieve /temp and /trashdir folders along with the rest of moodledata/folders?

QUESTION 2:

Is it safe to manually empty /temp and /trashdir folders on my server?

Thank you for your help.