What is warehouse?

In idt while sstudying customs topic v come accross warehousing provisions as per which the imported goods can be stored in a warehouse, withdout payment of duty.... every time da provision speaks abt warehouse, I get this doubt, "whose warehouse?"... is it company's own warehouse or does customs authorities have a separate warehouse of their own?? It may be a silly question but I wish to get it clarified. Thank you!!