Qu'est-ce que Screen Scraping ?

What is Screen Scraping?

Screen scraping is the process of extracting data by reading what is displayed on a computer screen, rather than accessing the data through APIs, databases, or file exports. The term originates from the era of mainframe terminals, where the only way to get data out of a legacy system was to programmatically read the characters displayed on the terminal screen.

Today, screen scraping has evolved to encompass several related techniques:

Screen Scraping vs. Web Scraping

While the terms are sometimes used interchangeably, they have distinct meanings:

Web scraping is generally faster and more reliable because it works with structured markup. Screen scraping is used when the underlying data source isn't accessible — legacy systems with no API, applications that render content as images, or heavily obfuscated pages where the HTML structure doesn't cleanly map to the visible data.

Modern Screen Scraping with Headless Browsers

The line between web scraping and screen scraping has blurred with headless browsers. When a scraper uses Playwright or Puppeteer to render a page, execute JavaScript, and then read the resulting DOM, it is performing a hybrid of both techniques. The browser renders the page as a user would see it, but the scraper extracts data from the rendered DOM rather than a screenshot.

This approach is particularly valuable for:

Use Cases and Limitations

Screen scraping remains relevant in specific scenarios:

Limitations include fragility (any UI change can break the scraper), performance (rendering is slower than parsing HTML), and accuracy (OCR-based approaches can misread characters).