The curious world of shipping containers: how these metal boxes revolutionized global trade

You may have never taken the time to consider it, but those enormous cargo containers you see stacked at ports, traveling on massive ships, endless trains, and trucks that are nearly impossible to overtake, are truly the hidden heroes of international trade. Without them, ordering from Amazon, importing clothing from China, or exporting olive oil to Japan would be both difficult and expensive—extremely expensive.

Today, we will share with you the history and interesting facts about these giants of transportation that, although they may appear to be simple metal boxes, actually contain a fascinating world within.

From trucks to ships: the origin of the modern container

The concept is not new: since ancient times, containers have been used for moving goods. However, everything changed in 1956. An American entrepreneur and transporter named Malcolm McLean, tired of the costs and time involved in loading individual boxes onto ships, had a revolutionary idea: What if all the cargo could be placed in large standardized metal boxes that could be transferred directly from trucks to ships?

To test his theory, McLean purchased two old vessels and adapted them to carry these metal containers, which shared the same dimensions as his truck trailers. The first voyage of a container ship, the “Ideal-X”, took place in April 1956, carrying 58 containers from Newark to Houston. The result exceeded expectations: shipping costs dropped from $5,83 per ton to just $0.16 per ton. This was a turning point that enabled globalization to take off.

The ISO standard for containers was established in 1961, which allowed for their global adoption. Today, over 90% of global commerce is transported by sea, and a large part of it moves in containers.

This concept of encapsulating cargo in a portable, secure, and reusable unit would later inspire the software industry to “package” content. However, that is a topic for another article 😉

How many containers operate in international trade and how are they moved?

According to data from UNCTAD (United Nations Conference on Trade and Development), in 2024, global container trade grew by 3.5%, marking a significant recovery after the modest 0.3% increase recorded in 2023. This upturn is attributed to the progressive improvement of supply chains following the impact of the pandemic, tensions in the Red Sea, and the normalization of flows along key routes such as Asia-Europe or the transpacific corridor.

Globally, it is estimated that there are over 40 million active containers, with the majority being manufactured in China, which produces 90% of the world supply. These containers move through an integrated network of more than 6,000 commercial ports and over 7,081 container ships, with a total capacity of 30.67 million TEUs (364 million deadweight tons). Their lifespan is between 10 and 15 years at sea, and much of their structure is recycled.

With nine international ports, Asia dominates container traffic. The most significant is the Port of Shanghai (China).

Types of containers: more than standard boxes

Although a container may be commonly imagined as a gray metal box of 20 or 40 feet, the universe of intermodal transport is much more diverse and sophisticated:

• Standard Container (Dry Van): The most widely used, ideal for dry or general cargo such as appliances, clothing, or industrial materials. It accounts for over 80% of the worldwide container fleet.
• Metal Containers: Similar to the standard types but not hermetically sealed and without refrigeration. These are commonly used for transporting garbage and waste by road.
• Reefer (Refrigerated): Essential for the cold chain. It transports products ranging from seafood to vaccines, maintaining temperatures between -25 °C and +25 °C, thanks to autonomous refrigeration systems connected to the ship’s or truck’s electrical system.
• Open Top: Without a rigid roof, this container allows for the transportation of goods with excess height, such as metal coils or wind turbine components.
• Flat Rack: Lacking both side and top walls, this type is used for heavy machinery, industrial vehicles, or large structures.
• Tank Container: With a cylindrical structure, this container is designed for bulk liquids such as wine, oils, fuels, or hazardous chemicals. It includes pressure valves, cleaning systems, and anti-corrosive protection.
• Flexi-tank: This is an alternative to the tank container for non-hazardous bulk liquids. It utilizes a standard 20-foot (dry van) container fitted with a disposable flexible bag, generally made of polyethylene. This solution provides a more economical and efficient option for certain liquid products, such as vegetable oils, wines, or juices, particularly along single-use routes.

And for several years now, we have witnessed the rise of intelligent containers. Outfitted with IoT sensors, they allow for real-time monitoring of temperature, humidity, door openings, GPS tracking, impact and vibration detection. Furthermore, they integrate with management systems and send alerts.

Companies such as Traxens, Orbocom, or Smart Containers Group lead this segment, which is becoming standard in sensitive sectors such as food, pharmaceuticals, or luxury goods.

Sizes and capacity

In addition to types, shipping containers are also classified by size and load capacity. Each of these models may come in different lengths, with the most common being the 45, 40, and 20-foot versions, as well as the high-capacity models. The container measurement unit is the TEU (twenty-foot equivalent unit), equal to 20 feet (6.10 m). Global capacities of ships, container terminals, or port cargo movements are measured in TEUs.

The 20-foot containers, which are the most standardized internationally, have a maximum gross weight of approximately 29 tons, which includes both the payload and the container’s own weight. In the case of 40-foot containers, the maximum gross weight rises to about 32 tons.

The giants of the ocean: who controls the world (literally)

Behind every container traveling around the globe stands a megacorporation pulling the strings—or more accurately, directing the ships. Maritime transport is dominated by a small group of large shipping companies competing for the crown of global logistics. These are some of the most prominent:

1. MSC (Mediterranean Shipping Company) – Switzerland. In 2024, MSC consolidated its position as leader with a capacity of 6.3 million TEUs, representing 20.2% of the global total. Its fleet reached 879 vessels, widening the gap over Maersk by 1.9 million TEUs.
2. Maersk – Denmark. With a capacity of 4.3 million TEUs and a fleet of 707 ships, Maersk maintains a 14.6% market share. In 2024, the company announced the “Gemini Cooperation” with Hapag-Lloyd, focusing on reducing stops and improving punctuality.
3. CMA CGM – France. In 2024, CMA CGM reported revenues of $55.4 billion, an 18% increase from the previous year. The company transported over 6 million TEUs in the third quarter, benefiting from increased volumes and higher freight rates.
4. COSCO Shipping – China. COSCO Shipping Lines transported 18.3 million TEUs in 2024, generating revenues of 130,909 million yuan, a 36.8% increase compared to the previous year. The company also expanded its fleet with 12 new ships, adding 230,000 TEUs of capacity.
5. Hapag-Lloyd – Germany. In 2024, Hapag-Lloyd transported 12.5 million TEUs, a 5% increase over the previous year. The company reached, for the first time, an operating capacity of 2 million TEUs, consolidating its market position.

Together, these companies manage more than 80% of global container traffic. We are talking about trillions (with a “t”) in the value of goods moved each year, from smartphones to automobiles, as well as coffee, textiles, and industrial components. And it is important to note, this sector generates over $500 billion annually, according to the consultancy Drewry.

A delay along any of these routes can trigger domino effects on a global scale: factories may halt production, supermarket shelves may remain empty, or prices may soar (recent examples include the container crisis, the war in Ukraine, or the attacks in the Red Sea and their consequences).

Impact on international trade and global economy

The container did not merely change the method of transporting goods; it transformed the entire economy. Thanks to containers, supply chains became more efficient, more cost-effective, and more secure. Shipping times were reduced, theft (previously common with loose cargo) declined, and customs procedures were simplified.

This enabled the relocation of production and the rise of eCommerce giants. Does something called Amazon sound familiar? Without containers, you would not receive that imported gadget at your home within 72 hours. In fact, the logistics cost to ship a full container from Asia to Europe is often lower than sending a single box by courier within your own country.

Furthermore, the container was instrumental in the creation of modern ports such as those in Shanghai, Singapore, or Rotterdam—true hubs that operate 24/7 as logistical factories with robotic cranes and automated management systems.

Fun facts you didn’t know about containers (and you’ll want to share)

• A container can hold up to 32 tons of cargo and can be stacked up to nine stories high on a ship.
• Some containers have been converted into homes, offices, bars, or even boutique hotels (industrial design is in vogue).
• Satellite tracking services exist that allow you to view your container’s real-time location (much like you would with your AliExpress order, but on an XXL scale).
• A “second-hand market” for containers exists, and you can purchase one from just $500 if you would like to have an apocalyptic shelter in your backyard.

What does the future hold?

With increasing pressure to reduce emissions and the pursuit of greener logistics, containers are evolving as well. Lighter, recyclable, and more efficient versions are being developed, and new transport methods are aiming to decarbonize through alternative fuels such as ammonia or green hydrogen.

And if you thought the metaverse had no place here, think again: companies like Maersk are exploring digital twins to optimize routes and times in real-time.

Photo: ChatGPT