Magento 2 – Is it safe to delete ‘var/vendor’ directory?

I quiet often come across suggestions in forums asking to delete all the directories (below) under var/ as a fix to other problems

var/cache
var/composer_home
var/log
var/page_cache
var/vendor
var/view_preprocessed

Is it safe to do this? Especially I am curious about var/vendor. Will this directory be recreated after I delete it?