An online learning platform is a digital environment where learners can access educational content such as video lessons, quizzes, and assignments. Instructors can create and manage courses, while students can browse available courses, enroll, and monitor their learning journey.

Examples of such platforms include Coursera and Udemy.

In this chapter, we will explore the low-level design of an Online Learning Platform in detail.

Let’s start by clarifying the requirements:

1. Clarifying Requirements

Before designing an online learning platform, it’s important to understand the expectations and boundaries of the system. This discussion helps ensure alignment between interviewer and candidate and keeps the design focused and purposeful.

1.1 Functional Requirements

• Instructors can create courses and add lectures and quizzes to them.
• Students can enroll in courses and track their progress.
• Upon completion, the instructor should be notified and a certificate should be issued to the student.
• The platform supports multiple enrollments per student and instructor.
• The system should track per-component progress and provide an overall progress percentage.

1.2 Non-Functional Requirements

• The system should follow object-oriented principles with proper separation of responsibilities.
• The system should be modular and extensible, capable of adding new content types or actions upon course completion in the future.
• The design should prioritize clarity, testability, and ease of extension.

After the requirements are clear, the next step is to identify the core entities that we will form the foundation of our design.

2. Identifying Core Entities