Unless you work in or have an interest in geospatial information or geography, the word GIS is a fairly unfamiliar term. Some people even ask, isn't it GPS, not GIS?

GPS (Global Positioning System) is a technique for calculating a receiver's position using signals from three or more satellites. When you hear GPS, you tend to think of navigation, but whether we realize it or not, GPS has deeply woven itself into daily life. Navigation, smartphone maps, tracking rider locations for delivery platforms, drone swarm flight, military science, and more. GPS permeates a wide range of domains and delivers its benefits there. Through GPS, we can catch a glimpse of what kind of power comes from digitizing space in this digital age of geospatial information.

GIS (Global Information System) refers, broadly, to every technology that deals with geospatial information, GPS included. Not just GPS, but every technology intertwined with space—maps, coordinate systems, and the like—can be grouped under the broad umbrella of GIS.

Since the advent of computers, humanity has been digitizing everything in the real world. We've already digitized everything we can see and hear. Ever since the desire to preserve fleeting moments as memories took hold, the people who manage and provide access to this kind of data have been raking in enormous amounts of money.

Digitizing audio and video essentially means being able to manipulate audio and video at will. Compositing static data like photos is now child's play. Looking at advanced video editing techniques—not to mention the controversial deepfake technology—can even make you feel as though the very concept of perception has been betrayed.

Any sufficiently advanced technology is indistinguishable from magic.

If video and photos deal with audio and video, GIS is a truly remarkable technology that digitizes space in the real world and lets us work with it. Right now it's common to work with data types like maps or location information, but in technologies where "space" is the main subject—like the metaverse and virtual reality that are in the spotlight these days—GIS will be at the very core of it.

If audiovisual digitization casts a magic spell over sound and sight, GIS can be said to cast a magic spell over the concept of space within the digital world.

...I wrote all that rather grandly, but I'm no GIS master—just an ordinary programmer who's dipped a toe into GIS.

It seemed like there was some demand for GIS at the company I moved to, so I figured I'd revive some of the skills I learned at my previous company and, as a kind of toy project, build a GIS service while documenting the related technology along the way.

Honestly, in Korea, GIS gets the short end of the stick compared to other technologies. As is typical with this kind of foundational technology, if you dig deep enough you end up in surveying or civil engineering, so unless you're someone with a real interest in the GIS field, it's awkward to go too deep. Even you, reading this right now, are probably in that boat. You want to be a developer—you definitely don't want to be a GIS researcher.

People go traveling and look at maps made of GIS, but the reality is that those who actually want to travel through GIS itself find there's precious little to see in Korea. They say other journeys are hard once you're on the road—but for GIS travelers, the hardship starts right at the trip-planning stage.

We were all beginners once.

You can't tell an elementary schooler who says "I want to get good at math!" to go solve Jeong-seok's Math straight away.

You can't tell a developer three days into a government-funded bootcamp who says "I want to get good at programming!" that "Oh yeah? Then go solve Level 5 problems on Programmers."

Everything has an entry point, and an order to follow. A child's thinking is best understood when you meet it at the child's eye level.

Though I'm still a fledgling programmer, I hope that through my experience, writing, and perspective, I can be even a small guide for developers who are just now starting their journey through OpenLayers.

• OpenLayers 6
• React
• GeoServer

• Let's look at how programming handles GIS!
• Let's build a GIS service environment with GeoServer!
• Let's serve up a GIS service with React + OpenLayers 6!
  • Since OpenLayers 6 is geared toward ESNext, React is a good fit.