Understanding Users, Sessions, and Traffic Sources in GA4
What Are Users, Sessions & Traffic Sources
To effectively use Google Analytics 4 (GA4) or any web analytics tool, you need to master three foundational metrics: Users, Sessions, and Traffic Sources. These are the building blocks of digital analysis — everything from campaign optimization to content strategy starts with understanding who is visiting your website, how often, what they do, and where they’re coming from.
In this module, we’ll break down each of these core concepts, show how they work together, and explain why they matter for your marketing strategy, UX design, and business growth.
What Are Users
A user is an individual who interacts with your website or app. In GA4, users are identified using cookies or device identifiers, and if configured properly, via login-based user IDs. Unlike page views or sessions, users help you track human behavior across time.
Types of users in GA4:
• New Users: First-time visitors to your platform
• Returning Users: People who have visited before
• Engaged Users: Users who spend more than 10 seconds, view at least 2 pages, or complete a conversion event
Why users matter:
• They represent your real audience — not just clicks or traffic volume
• Monitoring new vs. returning users shows how well you’re retaining visitors
• Segmentation by user type allows for personalization and better remarketing
Example: If 80% of your users are new and few return, you may need to improve content relevance or email follow-up to increase loyalty.
What Are Sessions
A session is a group of user interactions on your site that occur within a set time frame (typically 30 minutes). One user can have multiple sessions over different days — or even within the same day.
Sessions include:
• Page views
• Button clicks
• Form submissions
• Video plays
• Conversions
Key session metrics:
• Session Duration: How long users stay on your site
• Bounce Sessions: Visits where users leave after one interaction
• Engaged Sessions: Active sessions where users interact meaningfully
Why sessions matter:
• They help you measure engagement and content effectiveness
• Long sessions may indicate a deep interest in your offerings
• High bounce rates could point to UX or content issues
Example: If visitors are staying less than 30 seconds and bouncing, you might need to rework your landing page design or headline.
What Are Traffic Sources
Traffic sources tell you how people arrive at your website. GA4 breaks this down using Source, Medium, and Campaign data:
• Source: The origin (e.g., google, facebook, newsletter)
• Medium: The channel type (e.g., organic, paid, email)
• Campaign: The specific campaign name (if tracked via UTM links)
Main traffic source types:
• Organic Search: From search engines like Google or Bing
• Direct: Users who typed your URL or used bookmarks
• Referral: From other websites that link to you
• Paid Search: From Google Ads or other paid search platforms
• Social: From platforms like Facebook, Instagram, Twitter
• Email: From marketing newsletters or campaigns
Why traffic source data matters:
• It helps you identify your most valuable channels
• You can compare performance across platforms
• It shows you where to invest more (or less) budget and effort
Example: If organic search traffic is converting better than paid ads, it may be time to improve SEO instead of increasing ad spend.
How These Metrics Work Together
Users, sessions, and traffic sources are most powerful when combined. Here’s how they connect:
• A new user (user) visits your website by clicking on a Google ad (traffic source) and spends 4 minutes browsing your products (session)
• A returning user (user) comes back via an email link (traffic source) and purchases a product after visiting 3 pages (session)
By analyzing all three:
• You learn which source brings the best users
• You see how long sessions last per channel
• You uncover which users are most engaged — and why
Real-Life Case Example
• Company: Online Learning Platform
• Problem: Traffic was growing, but sign-ups were flat
• Insight: GA4 reports showed that most sessions came from social media (traffic source), but bounce rates were high and session durations were short
• Action: The company optimized its social landing pages with clearer headlines and stronger calls to action
Result: Session time increased by 30% and conversions improved by 18% within 3 weeks
Key Takeaways
• Users = Who is visiting your site or app
• Sessions = How they interact with it
• Traffic Sources = Where they came from
Understanding these metrics allows you to:
• Track audience growth and retention
• Evaluate marketing campaign performance
• Improve site engagement and user flow
• Target the right audience on the right platform
What You’ll Learn from This Module
By the end of this lesson, you will be able to:
• Define users, sessions, and traffic sources in GA4
• Differentiate between new and returning visitors
• Analyze traffic quality by source
• Identify trends that lead to conversions or drop-offs
• Use insights to improve acquisition and retention strategies
Final Thoughts
No matter how advanced your analytics gets, success starts with understanding the basics. Users, sessions, and traffic sources give you essential insight into how your digital presence is performing — and what needs to change.
Mastering these metrics ensures your web strategy isn’t based on guesswork, but on data that reflects real people and real behavior.
