From Tutorials-RaspberryPi:
For uploading files on a Raspberry Pi you should install a FTP server. Such a server is very useful if you use your Pi as a web server or even if you want to have a network storage, which can also be accessed outside of your network if an DNS server is installed.
However this tutorial is not only for web server but can also be used for easy file transfer between Raspberry Pi and your PC.
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