The MV Maersk Mc-Kinney Moller, the world's biggest container ship, arrives at the harbour of Rotterdam August 16, 2013 Reuters/Michael Koonen Shipping is vital for the global economy, with roughly 90% of all goods moved across the world by ships.

If shipping stops, so does the world economy.

The industry has been in the doldrums of late, however, with the global slowdown and the crash in the price of commodities hitting shipping firms hard. Things were so bad early in 2016 that the Baltic Dry Index, which tracks the cost of shipping goods and is often cited as a bellwether of the world economy, recently hit its lowest level in history.

But despite the shipping industry's problems, the number of active ships is still enormous — at any given time there are generally more than 50,000 merchant ships on the high seas, moving goods and commodities all over the place.

An interactive map, created by the data-visualisation firm Kiln and University College London's Energy Institute, shows the movements of all ships in the global merchant fleet during 2012, the most recent year with complete data. It illustrates the vast scale of shipping, as well as the complex nature of the industry, using a series of filters.

Here's how the map looks with every single filter switched off, meaning all routes and ships are shown at once:

Shipmap.org

The map allows users to filter ships by five types, each given a colour:

Container (e.g. manufactured goods): yellow

Dry bulk (e.g. coal, aggregates): blue

Tanker (e.g. oil, chemicals): red

Gas bulk (e.g. liquefied natural gas): green

Vehicles (e.g. cars): purple

Kiln's map also shows the world's most important and busiest ports and the most commonly used shipping routes.

Here's how it looks when you filter things down to just container ships — those carrying shipping crates. Each dot represents an individual ship:

Shipmap.org

And this part of the map shows all of the globe's most crucial ports:

You can also delve deeper into individual parts of the world. Here's how things look in the English Channel, one of the busiest shipping routes:

And this is the Panama Canal, the quickest way between the Atlantic and Pacific oceans:

Along with being incredibly cool, and showing all the world's ships, the map has an environmental point, illustrating just how much fuel ships use, how much carbon dioxide they belch out into the environment, and how much damage that can potentially cause.

As a video accompanying the map says: "Commercial ships produce more than a million tonnes of CO2 per day. That's more than the whole of the UK, or Canada, or Brazil."

You can find the full interactive map here.