What Do Container Ships Carry: Everything You Need to Know

Container ships are one of the most recognizable symbols of global trade. If you’ve ever seen a vessel stacked high with colorful metal boxes, you’ve seen containerization in action. But what exactly do container ships carry, and how do they differ from other types of cargo vessels? 

In this blog post, we break down the basics of container ships, the types of cargo they transport, how containers work, and how this system transformed global shipping. 

What Are Container Ships? 

Obvious question, maybe, but we may as well start at the very beginning!  

Container ships are cargo vessels specifically designed to carry standardized shipping containers. These containers are metal boxes used to transport goods safely and efficiently by sea, rail, and truck. 

Unlike traditional cargo ships, which might carry loose cargo or individually handled goods, container ships are built so that containers can be stacked in vertical cell guides below deck and in secured stacks on deck. 

The key advantages of container ships include: 

• Faster loading and unloading 

• Standardized cargo handling 

• Improved cargo security 

• Reduced labor costs 

• Lower risk of damage or theft 

Container shipping now accounts for the majority of manufactured goods transported worldwide. 

Different Types of Container Ships 

Container ships vary in size depending on the trade routes they serve. 

Feeder Vessels 

• Hold up to 3,000 TEU (more on TEU below!) 

• Serve smaller ports and regional routes 

• Transfer cargo to larger hub ports 

• Feeder vessels are so called because they ‘feed’ larger ships with containers 

Panamax and Post-Panamax 

• Hold between 4,000 to 10,000 TEU 

• Designed for major international routes 

• The word ‘Panamax’ is a combination of ‘Panama’ and ‘maximum’. This is the maximum size of ship that is able to pass through the locks of the Panama Canal. 

• Post-Panamax vessels are called so because they exceed the size limits of the original Panama Canal locks, created in 1914. 

Ultra Large Container Vessels (ULCVs) 

• Hold from18,000 to 24,000+ TEU 

• Operate mainly between Asia and Europe 

• Require deep-water ports and advanced infrastructure 

Larger ships benefit from economies of scale but are limited to major ports. 

How Are Container Ships Different from Other Cargo Ships? 

It can be easy to confuse container ships with other cargo vessels, but they serve very different purposes. 

Container Ships 

• Carry standardized containers 

• Transport manufactured and packaged goods 

• Flexible cargo types 

Bulk Carriers 

• Carry unpackaged bulk commodities – hence the name bulk carrier 

• Examples: coal, grain, iron ore 

• Cargo is loaded directly into large holds 

Tankers 

• Carry liquid cargo 

• Examples of cargo include crude oil, chemicals, and LNG and LPG gasses 

• Have specialized tanks and pumping systems 

• Are divided into types by cargo – for example, gas carriers, chemical tankers, and oil tankers 

General Cargo Ships 

• Carry mixed goods that may not fit in containers 

• Often use cranes for loading 

Container ships are unique because they rely on standardized containers rather than carrying goods loose or in dedicated tanks. 

What are Shipping Containers? 

Shipping containers are standardized steel boxes designed for intermodal transport. That means they can move easily between ship, truck, and rail without unloading the cargo inside.  

Standard Container Sizes 

• 20-foot container (1 TEU) 

• 40-foot container (2 TEU) 

TEU stands for Twenty-foot Equivalent Unit and it’s the standard measurement used to describe container capacity. For example, a 10,000 TEU ship can carry the equivalent of 10,000 20-foot containers. 

Fun fact: Those working in the maritime industry often refer to shipping containers as ‘boxes’ and it’s for this reason that container ships are also sometimes called ‘boxships’.  

Different Types of Shipping Containers 

Not all containers are the same and different cargo types require different container designs. 

Dry Containers 

• The most common type 

• Used for general cargo 

• Fully enclosed 

Reefer Containers 

• Short for refrigerated containers 

• Used for food, pharmaceuticals, and temperature-sensitive goods 

• Plugged into an onboard power supply 

Open-Top Containers 

• No solid roof 

• Used for oversized cargo 

• Loaded by crane 

Flat Rack Containers 

• No side walls or roof 

• Used for heavy machinery and vehicles 

Tank Containers 

• Designed to carry liquids 

• Used for chemicals and food-grade liquids 

High Cube Containers 

• Slightly taller than standard containers 

• Used for lightweight but bulky cargo 

This variety of different containers enables ships to transport a wide range of goods safely. 

A Brief History of Containerization 

Before containers, cargo was loaded piece by piece in a process known as breakbulk shipping. This was slow, labor-intensive, and prone to theft and damage. 

In 1956, an American entrepreneur named Malcolm McLean introduced the first standardized shipping container system. His innovation allowed entire truck trailers to be loaded onto ships without unloading their contents. 

Containerization revolutionized global trade by: 

• Dramatically reducing port time 

• Lowering shipping costs 

• Improving security 

• Enabling global supply chains 

By the 1970s, container ports were expanding worldwide, and today container shipping is the backbone of modern commerce. 

What Do Container Ships Actually Carry? 

As we’ve already mentioned, container ships transport a vast range of goods. In fact, almost anything that can fit inside a container can be shipped this way, including: 

Consumer Goods 

• Electronics 

• Clothing and textiles 

• Furniture 

• Household appliances 

There’s a very high chance that you’re wearing clothing, reading this blog post on a device, and sitting on a chair that have all been transported by container ship. 

Industrial Equipment 

• Spare parts 

• Machinery components 

• Tools 

Automotive Cargo 

• Car parts 

• Engines 

• Some vehicles (in specialized containers), although most cars and trucks will be transported by car carrier (PCC) or a car and truck carrier (PCTC) 

Food and Agriculture 

• Frozen meat and seafood 

• Fruit and vegetables 

• Dairy products 

• Grains in packaged form 

Pharmaceuticals 

• Vaccines 

• Medical equipment 

• Temperature-controlled medicine 

Retail and E-Commerce Products 

• Packaged consumer items 

• Seasonal goods 

• Online retail shipments 

Because containers protect cargo from weather and handling damage, they are also ideal for high-value manufactured goods. 

How Containers are Loaded 

Containers are loaded according to a detailed stowage plan that considers: 

• Weight distribution 

• Port sequence 

• Dangerous goods regulations 

• Stability requirements 

Heavy containers are usually placed lower in the hold. Dangerous goods must follow international regulations. Reefer containers are positioned near power outlets. 

Modern loading operations use large ship-to-shore cranes and sophisticated software to ensure efficiency and safety. 

Why Container Shipping is So Important 

Container ships make global trade possible at scale. Without them: 

• International supply chains would slow dramatically 

• Consumer prices would rise 

• Manufacturing networks would struggle 

They connect producers and consumers across continents in a standardized, efficient system. 

And while container ships may look simple (and often quite colorful) from a distance, they represent one of the most important innovations in modern trade. From food and electronics to medical supplies and industrial machinery, the containers stacked high on deck carry the goods that keep the global economy moving. 

Frequently Asked Questions 

What is the most common cargo carried on container ships? 

Manufactured goods such as electronics, clothing, and consumer products are the most common cargo types. 

Can cars be shipped in containers? 

Yes. Some vehicles are shipped in containers, especially luxury or high-value cars. However, most cars are transported on specialized car carriers. 

How many containers can a large ship carry? 

Ultra large container vessels can carry more than 24,000 TEU, which equals 24,000 20-foot containers. 

Are containers waterproof? 

Yes. Standard containers are designed to be weather-resistant and protect cargo from rain and sea spray. 

Do container ships carry dangerous goods? 

Yes, but strict international rules apply under the International Maritime Dangerous Goods (IMDG) Code to ensure safe storage and segregation. 

Why are container ships so large? 

Larger ships reduce cost per container through economies of scale, especially on high-volume trade routes.