Introduction to the Course

Let's begin with an overview of the course, its prerequisites, and its intended audience.

What is financial market data?

A financial market is where traders can exchange financial securitiesAny financial tool that has monetary value and can be traded., such as stocks and cryptocurrency. Financial market data provides information related to the price of securities. This includes opening and closing prices, as well as the highest and lowest prices of securities. This data is crucial for traders to make important predictions and decisions.

In this course, we’ll learn about the Polygon API, which provides various endpoints to fetch financial market data.

What is an API?

An API is a software gateway that allows different software components to communicate with each other. It helps expose the capabilities of an application to the outer world, allowing for programmatic access to the application’s data.

Consider the case of a service like Polygon that provides financial market data. Building and exposing an API for this service will allow others to programmatically fetch the data this service offers, such as the details of stock splits.

Press + to interact
How an API works
How an API works

Many popular services like YouTube, Reddit, and Google Maps also provide APIs for extended use cases. These services allow authorized clients to access their resources.


This course assumes you have the following:

  1. Basic knowledge of APIs and how they work.

  2. Fundamental knowledge of the JavaScript programming language.

  3. Basic understanding of the terminologies used in the stock market.

Intended audience

This course is for any individual who wants to learn how to use and integrate the Polygon API in JavaScript. The target audience for this course is:

  • Students who are new to the world of APIs and want to understand their basic usage.
  • Professionals who have extensive experience with other similar APIs and want to explore the Polygon API.