Netscape Navigator vs Internet Explorer

Basis	Netscape Navigator	Internet Explorer (IE)
Rendering engine	Early versions used Netscape's own engine; later Mozilla development led to Gecko	Major Windows versions used Microsoft's Trident engine
Proprietary features	Included Netscape-specific extensions and early web APIs	Supported Microsoft-specific extensions and, in some versions, ActiveX
Security	Security evolved across versions; scripting and plug-ins introduced risks	Windows integration and ActiveX expanded capabilities and potential attack surface
Standards	Differences in HTML/CSS/JavaScript behaviour caused compatibility issues	Non-standard behaviours and version differences also caused compatibility issues
Historical impact	One of the first widely used graphical browsers	Became dominant during the browser wars, partly through Windows integration

During the browser wars, developers sometimes used browser detection and separate code paths because browsers interpreted HTML, CSS and JavaScript differently. Proprietary APIs and inconsistent standards support meant a page might work in one browser and fail in another.

Competition helped popularize the Web but also fragmented it. Open standards, browser testing, progressive enhancement and later standardization efforts improved interoperability.

Conclusion: Both browsers shaped early web development. Their differences demonstrate why standards compliance and cross-browser testing matter. Details varied by version, and both products are now historical.