# Selenium — Browser Automation Framework and Ecosystem

> Selenium is the original browser automation framework for testing web applications. WebDriver API supports Chrome, Firefox, Safari, Edge across Java, Python, C#, Ruby, JavaScript. The industry standard for E2E web testing since 2004.

## Install

Save the content below to `.claude/skills/` or append to your `CLAUDE.md`:

## Quick Use

```bash
pip install selenium
# Download ChromeDriver or use webdriver-manager
pip install webdriver-manager
```

```python
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.chrome.service import Service
from webdriver_manager.chrome import ChromeDriverManager

driver = webdriver.Chrome(service=Service(ChromeDriverManager().install()))
driver.get("https://tokrepo.com")

# Find and interact
search = driver.find_element(By.CSS_SELECTOR, "input[type=search]")
search.send_keys("react")
search.submit()

# Assert
assert "React" in driver.page_source

driver.quit()
```

## Intro

Selenium is the original browser automation framework for web application testing. Created by Jason Huggins at ThoughtWorks in 2004. The WebDriver API became a W3C standard and is implemented by every major browser vendor. Supports Chrome, Firefox, Safari, Edge across Java, Python, C#, Ruby, and JavaScript.

- **Repo**: https://github.com/SeleniumHQ/selenium
- **Stars**: 34K+
- **Language**: Java (core)
- **License**: Apache 2.0

## What Selenium Does

- **WebDriver** — W3C standard browser control protocol
- **Cross-browser** — Chrome, Firefox, Safari, Edge
- **Multi-language** — Java, Python, C#, Ruby, JS
- **Selenium Grid** — distributed parallel testing
- **Selenium IDE** — record and playback browser extension
- **Wait strategies** — explicit and implicit waits
- **Actions API** — mouse, keyboard, drag-drop
- **Screenshots** — capture on failure

## Comparison

| Tool | Protocol | Cross-browser | Multi-lang |
|---|---|---|---|
| Selenium | WebDriver (W3C) | All | 5 |
| Playwright | CDP/WebDriver | 3 | 4 |
| Cypress | In-browser | 4 | JS only |
| Puppeteer | CDP | Chromium | JS/Python |

## FAQ

**Q: Selenium vs Playwright?**
A: Playwright is more modern (auto-wait, better DX); Selenium is more mature with more language support and is the W3C standard. Legacy projects or Ruby/C# tend to pick Selenium; new projects tend to pick Playwright.

## Sources

- Docs: https://www.selenium.dev/documentation
- GitHub: https://github.com/SeleniumHQ/selenium
- License: Apache 2.0

---
Source: https://tokrepo.com/en/workflows/selenium-browser-automation-framework-ecosystem-42404d19
Author: Script Depot