1.截图工具：snipaste
https://www.snipaste.com/download.html

2.各种格式电子书阅读工具：SumatraPDF
https://www.sumatrapdfreader.org/download-free-pdf-viewer

3.画图工具：draw.io-ia32-15.3.8-32bit.exe
https://github.com/jgraph/drawio-desktop

4.视频查看工具：PotPlayer
https://potplayer.daum.net/