Imagine a world where your credit card would not fit into every cash machine or
where you could not just stroll into a shop and find the right lightbulb for your lamp.
A world without telephone codes, country and currency codes and access to the
Internet. How would you know where a call came from, or how to reach a specific
region? If we didn't have standards, communication between people, machines,
parts and products would be extremely difficult.

For example, graphical symbols display important information quickly and clearly,
no matter what language we speak or read – be they wash and care instructions
on clothes, emergency evacuation signs, or electrical equipment instructions. But
if everyone used different symbols for the same message, they would not serve
their purpose!

Technology also needs standards to communicate. Have you ever wondered how
your computer sends your documents to a printer from a different manufacturer?
Standards set out common rules and parameters so that products can work with
each other. Standard file formats like MPEG and JPEG standard enable you to
share videos and photos with family and friends using technology from different
vendors.

Now imagine how difficult it would be to order products and parts from international
suppliers if we didn’t have standardized units of measurement. “Small”, “medium”
and “large” mean different things to different people.

Not only are standards good for trade, they also make it easy for people around
the world to work together.

International Standards are like the Rosetta stone of technology. They are essential
for products to work together smoothly and for people to communicate easily. When
standards are in place things just work, but if they are not used we instantly notice it.
In a world without standards, routine activities we take for granted, like making a call,
surfing the Web or using our credit cards when we travel, would be much more
complicated, nearly impossible.

Source: http://www.iso.org/iso/world-standards-day2015