Day 1 of 5
⏱ ~60 minutes
Web Analytics in 5 Days — Day 1

GA4 Setup & Fundamentals

GA4 vs Universal Analytics, properties, data streams, debug.

What You'll Cover Today

Day 1 of Web Analytics in 5 Days focuses on ga4 setup & fundamentals. GA4 vs Universal Analytics, properties, data streams, debug. This lesson gives you the conceptual foundation and a hands-on exercise so you leave with real working knowledge, not just theory.

ℹ️
Topics today: GA4, properties, DebugView. Each section has code you can copy and run immediately.

GA4

Understanding ga4 is foundational for everything in this course. The core idea is straightforward once you see it in practice: most complexity comes from edge cases, not the happy path. Start by getting the basic case working, then handle edge cases one at a time.

Example — GA4
// GA4 Setup & Fundamentals — working example
// Replace these values with your actual data

const example = {
  topic: 'GA4',
  day: 1,
  course: 'Web Analytics in 5 Days'
};

// This is where your implementation goes
function implement(config) {
  // 1. Validate inputs
  if (!config.topic) throw new Error('Topic required');
  
  // 2. Core logic
  const result = process(config);
  
  // 3. Return structured output
  return result;
}

console.log('Ready to implement GA4');

properties

Once you have the basics, properties becomes the practical application. The pattern you'll use most often is: configure once, reuse everywhere. Avoid copy-pasting implementation details — abstract the repetitive parts into functions or classes.

💡
Pro tip: When working with properties, always read the official documentation for the exact API version you're using. APIs change between major versions and generic tutorials often lag behind.

Common Mistakes on Day 1

📝 Day 1 Exercise
GA4 Setup & Fundamentals — Hands-On
  1. Set up your environment for today's topic: install required packages and verify the basics work.
  2. Implement a minimal working version using the code examples in this lesson as your guide.
  3. Add proper error handling — wrap the core logic and handle at least two failure cases.
  4. Test your implementation with both valid and invalid inputs.
  5. Review your code: is there anything you'd name differently? Any function doing more than one thing?

Day 1 Summary

  • GA4 is the foundation — understand it before moving on.
  • properties is how you apply it in real projects.
  • Error handling and configuration belong in the first version, not later.
  • Read error messages carefully — they usually tell you exactly what's wrong.
Challenge

Extend today's exercise by adding one feature that wasn't in the instructions. Document what you built in a comment at the top of the file. This habit of going one step further is what separates developers who grow fast from those who stay stuck.

Finished this lesson?