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免费且开源的文件对比比较和合并工具 WinMerge is an Open Source differencing and merging tool for Windows. WinMerge can compare both folders and files, presenting differences in a visual text format that is easy to understand and handle.

里面有超多全球各国的矢量地图，分类详细，而且支持多种不同格式的文件下载，完全免费使用。 d-maps: Free maps, free outline maps, free blank maps, free base maps, all the countries of the world, high resolution GIF, PDF, CDR, SVG, WMF

超5.7万版权过期（Publicdomain）的电子书，免费、合法、无需注册 Free eBooks | Project Gutenberg

完全免费免版权高质量照片网站 Startup Stock Photos are free startup, office, and tech stock photos ready for your next project. Used by millions. Make something awesome.

Polarr's advanced online photo editor offers desktop quality tools for pros and hobbyists without the need to downloading any app.

提供数百万个三维模型，登录后就能免费下载 The GrabCAD platform drives additive manufacturing at scale through connected solutions, including GrabCAD Print, GrabCAD Shop & the GrabCAD SDKs.

一个专门收集计算机，编程，数学，工程和技术书籍，讲义和教程等专业知识电子书的链接网站，内容全免费，有13个顶级类别和200多个子类别 Links to Free Programming, Computer, Mathematics, Technical eBooks and Lecture Notes all over the World, Directory of online free programming, computer, engineering, mathematics, technical books, ebooks, lecture notes and tutorials. Very well categorized. Equipped with advanced search engines.

免费高清视频资源 Download Free Quality HD stock footage and stock video. Hundreds of free stock footage clips..

国际知名站点，提供大量英文字体免费下载 Archive of freely downloadable fonts. Browse by alphabetical listing, by style, by author or by popularity.

一个音效素材搜索引擎，而且支持中文界面，有详细的音效分类，可以快速找到自己想要的音效素材。 Search the web for free sounds and sound effects

能极速压缩80%的图片体积，而不损害其质量 Picdiet is a fast and robust online batch image filesize compressor written in JavaScript, images are compressed in your browser, completely free

音效搜索引擎 Search the web for free sounds and sound effects