Your developer mentions “containers” and “Kubernetes” and suddenly the conversation sounds like a foreign language. You nod along, wondering if you really need to understand this stuff.
Here’s the honest answer: you probably don’t need to understand the technical details. But you do need to understand enough to ask good questions and recognise when containers are solving a real problem versus when they’re adding unnecessary complexity.
This guide explains containerization in plain English—what it is, why it exists, and the only questions you actually need to ask.
TL;DR: The 30-Second Version
What containers are: A way to package software so it runs identically everywhere, solving “it works on my machine” problems.
What Docker is: The tool that creates and runs containers.
What Kubernetes is: A system for managing lots of containers across many servers.
Do you need them? Maybe. Containers are genuinely useful for complex applications. But for simple setups, they add complexity without much benefit.
The one question to ask: “What specific problem do containers solve for us that we can’t solve more simply?”
What Are Containers, Really?
Imagine you’re shipping furniture overseas. You could send each piece individually—the chair, the table, the lamp—and hope everything arrives intact and fits together at the destination. Or you could pack everything into a shipping container: the furniture, the assembly tools, even the instructions.
Software containers work the same way.
Instead of installing an application and hoping the destination server has the right software versions, configurations, and dependencies, you package everything together:
- The application code
- All required libraries and dependencies
- Configuration files
- Everything needed to run
This container then runs identically wherever you put it—developer laptop, test server, production cloud.
The Problem Containers Solve
Before containers, getting software to work consistently was surprisingly hard. A common scenario:
- Developer builds application on their Mac
- Works perfectly on their machine
- Deploy to Linux server
- Breaks
- Hours of debugging to figure out what’s different
Containers eliminate this by ensuring the environment is identical everywhere.
Containers vs Virtual Machines
You might have heard of virtual machines (VMs). Containers are often compared to them:
| Aspect | Virtual Machine | Container |
|---|---|---|
| What’s included | Entire operating system | Just the app and dependencies |
| Size | Gigabytes | Megabytes |
| Startup time | Minutes | Seconds |
| Resource usage | Heavy | Light |
| Isolation | Complete | Process-level |
Simple analogy: VMs are like separate houses (each with their own foundation, plumbing, electrical). Containers are like apartments in a building (shared infrastructure, separate living spaces).
Docker and Kubernetes: The Key Players
You’ll hear two terms constantly: Docker and Kubernetes. Here’s what they actually mean.
Docker
Docker is the technology that creates and runs containers. It’s like the shipping container format standard—the specification for how containers should be built and what they should contain.
When someone says they’re “using Docker,” they mean they’re packaging their applications into containers using Docker’s tools.
What Docker does:
- Creates container images (the packaged software)
- Runs containers from those images
- Provides tools for building and managing containers
Kubernetes
Kubernetes (often abbreviated K8s) is a system for managing containers at scale. If Docker is the container, Kubernetes is the shipping port—scheduling which containers run where, moving them when needed, replacing them when they fail.
What Kubernetes does:
- Runs containers across multiple servers
- Automatically restarts failed containers
- Scales containers up or down based on demand
- Manages networking between containers
- Handles rolling updates and deployments
Do You Need Kubernetes?
Here’s where business owners often get oversold.
Kubernetes is designed for: Large-scale applications running dozens or hundreds of containers across multiple servers, needing automatic scaling and self-healing.
Kubernetes is overkill for: Simple applications, small teams, straightforward deployment needs.
The problem: Kubernetes has become trendy, so it gets recommended even when simpler solutions would work fine. It adds significant complexity and requires ongoing expertise to manage.
Questions to ask if someone recommends Kubernetes:
- “How many containers will we be running?”
- “What would happen if we used a simpler deployment approach?”
- “Who will manage Kubernetes ongoing? What’s the cost of that expertise?”
When Containers Make Sense
Containers genuinely solve real problems. Here’s when they’re worth considering:
Good Reasons to Use Containers
1. Multiple services that need to work together
If your application is split into multiple services (sometimes called “microservices”), containers make it easier to develop, deploy, and scale each piece independently.
2. Consistent environments are critical
If you’ve been burned by “works on my machine” problems, containers guarantee consistency between development, testing, and production.
3. You need to scale specific parts independently
Containers make it easy to run more copies of just the parts that need more capacity, rather than scaling everything.
4. Your team is already experienced with containers
If your developers already know containers well, the learning curve cost is already paid.
Times to Question Container Recommendations
1. Simple applications
A basic web application with a database doesn’t necessarily need containers. Traditional deployment works fine.
2. Small team without container experience
The learning curve is significant. If your team needs to learn containers from scratch for a simple project, the overhead might not be worth it.
3. “Everyone is doing it”
This is not a reason. Technology choices should be based on your specific needs, not trends.
4. You’re told you need Kubernetes for 2-3 containers
Kubernetes makes sense at scale. For small deployments, simpler container management tools work fine.
You probably don’t need containers if:
- You’re running a WordPress or basic CMS site
- Your application is a single service with a database (not microservices)
- You’re building a small internal CRUD app
- Your deployment process works fine without them
Containers solve real problems—but if you don’t have those problems, they add complexity for no benefit.
The Questions to Ask Your Technical Team
If containers or Kubernetes come up in technical discussions, here’s what to ask:
About Containers Generally
“What specific problem do containers solve for us?”
- Good answer: Specific issues with deployment consistency, scaling, or environment management
- Red flag: “It’s the modern way” or “best practices”
“What would happen if we didn’t use containers?”
- Good answer: Honest comparison of trade-offs
- Red flag: Can’t articulate the alternative
“What’s the ongoing cost of managing containers?”
- Good answer: Staff time, tooling costs, expertise requirements
- Red flag: “Containers are free” (the tech is free; the management isn’t)
About Kubernetes Specifically
“How many containers are we planning to run?”
- 2-5 containers: Kubernetes is probably overkill
- 20+ containers: Kubernetes might make sense
- 100+ containers: Kubernetes is likely justified
“Who will manage Kubernetes? What’s that cost?”
- Good answer: Specific team or managed service with costs
- Red flag: “It manages itself” (it doesn’t)
“What’s the simplest alternative that would work?”
- There’s almost always a simpler option. Understand why you’d choose the complex one.
Managed Container Services
If containers do make sense for your situation, you don’t have to manage the complexity yourself. Managed services remove most of the operational pain. Major cloud providers offer managed container services that handle much of the complexity:
Managed Kubernetes:
- AWS EKS (Elastic Kubernetes Service)
- Google GKE (Google Kubernetes Engine)
- Azure AKS (Azure Kubernetes Service)
Simpler container hosting:
- AWS ECS (Elastic Container Service)
- Google Cloud Run
- Azure Container Instances
- Fly.io, Render, Railway
The trade-off: Managed services cost more but require less expertise. For most small businesses, the premium is worth it.
Key Takeaways
Containers are a packaging technology. They bundle software with everything it needs to run, ensuring consistency across environments.
Docker creates and runs containers. It’s the standard tool for working with containers.
Kubernetes manages containers at scale. It’s powerful but complex, and often overkill for small deployments.
You don’t need to understand the technical details. But you should ask why containers are being recommended for your specific situation.
Simpler is often better. If someone can’t clearly explain why you need containers or Kubernetes, you might not need them.
The key question: “What specific problem does this solve for us?”
Related Reading
- IaaS, PaaS, SaaS Explained — Understanding cloud service models
- Cloud Migration Checklist — Planning a move to cloud
- The Hidden Costs of Cloud — Managing cloud spending
- Architecting Robust Cloud Infrastructure — Cloud architecture basics
Need a Second Opinion on Kubernetes?
If your team is pushing for Kubernetes and you’re not sure whether it’s overkill, send me the proposal. I’ll flag complexity you don’t need and suggest simpler alternatives where they exist.
