These free alternative tools for Microsoft Visio help you in making flow charts, ER diagrams, layouts, GUI prototyping, data visualization. These are available for Mac and Linux as well. So no more dependence on pricey Microsoft Visio. Use any of these replacements and get going!
Learn how to detect whether a web page URL has 301, 302 or 307 redirection code working on it. It is useful as browsers don't let you see such redirection.
Learn how to know if a website is safe for browsing. Use this tool from Google Safe Browsing Diagnostic to test the link safety before you go to site.