YouTip

## 404 NOT FOUND! Sorry, the page you requested was not found! The 404 page is an essential component of any website, playing a crucial role in user experience and SEO optimization. A 404 page appears when users visit a page that does not exist or has been deleted on the website, resulting in the server returning a 404 error. If the site administrator does not set up a proper 404 page, dead links will appear, which hinders search engine indexing when crawlers encounter such URLs. ## Origin of the 404 Not Found Error It is said that before the Third Industrial Revolution, the Internet existed as a large centralized database located in Room 404. At that time, all requests were handled manually by staff. If the requested file was not found in the database—or if the requester entered an incorrect file number—the user would receive the response: "room 404: file not found." After the rise of the Internet, people gradually adopted "404" as the standard error code indicating that the server could not locate the requested file. Of course, there is no actual evidence that Room 404 ever existed. ## Two Major Benefits of Setting Up a 404 Page * Guide users not to leave the website, thereby enhancing user experience. * Prevent dead links on the website. For more information, see (https://example.com/http/http-status-codes.html). !(https://example.com/wp-content/themes/tutorial/assets/img/404.jpg) (javascript:void(0);) * [Python / Data Science](javascript:void(0);) * (https://example.com/python3/python3-tutorial.html "Python Tutorial") * [Python2.x Tutorial](https://example.com/python/python-tutorial.html "Python2.x Tutorial") * (https://example.com/fastapi/fastapi-tutorial.html "FastAPI Tutorial") * (https://example.com/flask/flask-tutorial.html "Flask Tutorial") * (https://example.com/django/django-tutorial.html "Django Tutorial") * (https://example.com/numpy/numpy-tutorial.html "NumPy Tutorial") * (https://example.com/pandas/pandas-tutorial.html "Pandas Tutorial") * (https://example.com/scipy/scipy-tutorial.html "SciPy Tutorial") * (https://example.com/matplotlib/matplotlib-tutorial.html "Matplotlib Tutorial") * (https://example.com/dash/dash-tutorial.html "Dash Tutorial") * (https://example.com/jupyter-notebook/jupyter-notebook-tutorial.html "Jupyter Notebook Tutorial") * (https://example.com/pillow/pillow-tutorial.html "Pillow Tutorial") * (https://example.com/qt/qt-tutorial.html "Quantitative Trading") * (https://example.com/r/r-tutorial.html "R Tutorial") * (https://example.com/julia/julia-tutorial.html "Julia Tutorial") * [AI / Intelligent Development](javascript:void(0);) * [AI Agent（Intelligent Agent)](https://example.com/ai-agent/ai-agent-tutorial.html "AI Agent（Intelligent Agent)") * [AI（AI)](https://example.com/ai/ai-tutorial.html "AI（AI)") * (https://example.com/codex/codex-tutorial.html "Codex Tutorial") * (https://example.com/claude-code/claude-code-tutorial.html "Claude Code") * (https://example.com/opencode/opencode-tutorial.html "OpenCode") * [Skills（Skills)](https://example.com/skills/skills-tutorial.html "Skills（Skills)") * (https://example.com/ollama/ollama-tutorial.html "Ollama Tutorial") * (https://example.com/tensorflow/tensorflow-tutorial.html "TensorFlow Tutorial") * (https://example.com/pytorch/pytorch-tutorial.html "PyTorch Tutorial") * (https://example.com/sklearn/sklearn-tutorial.html "Scikit-learn Tutorial") * (https://example.com/ml/ml-tutorial.html "Machine Tutorial") * (https://example.com/langchain/langchain-tutorial.html "LangChain") * (https://example.com/nlp/nlp-tutorial.html "Natural Language Processing NLP") * (https://example.com/opencv/opencv-tutorial.html "OpenCV Tutorial") * (https://example.com/selenium/selenium-tutorial.html "Selenium Tutorial") * (https://example.com/playwright/playwright-tutorial.html "Playwright Tutorial") * (javascript:void(0);) * (https://example.com/html/html-tutorial.html "HTML Tutorial") * (https://example.com/html/html5-intro.html "HTML5 Tutorial") * (https://example.com/css/css-tutorial.html "CSS Tutorial") * (https://example.com/css3/css3-tutorial.html "CSS3 Tutorial") * (https://example.com/js/js-tutorial.html "JavaScript Tutorial") * (https://example.com/htmldom/htmldom-tutorial.html "HTML DOM Tutorial") * (https://example.com/typescript/ts-tutorial.html "TypeScript Tutorial") * (https://example.com/ajax/ajax-tutorial.html "AJAX Tutorial") * (https://example.com/json/json-tutorial.html "JSON Tutorial") * (https://example.com/tailwindcss/tailwindcss-tutorial.html "Tailwind CSS Tutorial") * (https://example.com/bootstrap4/bootstrap4-tutorial.html "Bootstrap4 Tutorial") * (https://example.com/bootstrap5/bootstrap5-tutorial.html "Bootstrap5 Tutorial") * (https://example.com/foundation/foundation-tutorial.html "Foundation Tutorial") * [Vue.js Tutorial](https://example.com/vue2/vue-tutorial.html "Vue.js Tutorial") * (https://example.com/vue3/vue3-tutorial.html "Vue3 Tutorial") * (https://example.com/react/react-tutorial.html "React Tutorial") * [Next.js Tutorial](https://example.com/nextjs/nextjs-tutorial.html "Next.js Tutorial") * (https://example.com/angularjs/angularjs-tutorial.html "AngularJS Tutorial") * (https://example.com/angularjs2/angularjs2-tutorial.html "Angular Tutorial") * (https://example.com/jquery/jquery-tutorial.html "jQuery Tutorial") * (https://example.com/jqueryui/jqueryui-tutorial.html "jQuery UI Tutorial") * (https://example.com/jeasyui/jqueryeasyui-tutorial.html "jQuery EasyUI Tutorial")