Shipping containers are all different colours, with company emblems on them as well and... some are bright and shiny.
Your from Singapore which is the 2nd. largest port in the world so you should be able to see plenty of them being loaded and unloaded at the docks at places like Pasir Panjang etc.
When ships encounter bad weather they are frequently washed overboard and then float around and become a danger to the navigation of other vessels and maybe a source of pollution as well.
Hope this has given you some food for thought......