The Internet is running out of IP addresses (ipv4, but years after ipv6 came out we still haven't switched over to it). This is realer than Peak Oil. And so most of us are connected to the Internet with an IP address shared with many other people, with many devices seen by the outside world as having one address.

But more locally, behind a router or gateway or firewall, we all have unique addresses and names to identify each other by. But only locally.

And so each of our devices have two or more possible IP addresses. Each computer should have a local IP address, its main...

Have you ever looked at an external drive with folders created on a Mac but then loaded on Windows or Linux? If you look carefully (turn on viewing of hidden and system files) you'll see a file beginning with ._ for some or many of your files, varying by file type. What are these mysterious '._xxx' files?

Mac OSX Resource Forks

Those ._ files are called resource forks. Resource forks are specific to Mac filesystems. They don't take up too much space and can contain useful data about your files. But deleting them also won't delete your files (the data...

FTP is the historically standard protocol for copying files from one computer to another over a network connection (TCP/IP, so any host on today's Internet, but it wasn't always the case). Many people including many developers learned how to use an FTP client on Windows in order to connect to a server and upload and download files.

Stop using FTP!

FTP is not secure for the same reason that HTTP is not secure and why there's a movement (Let's Encrypt) to move every website to use TLS, i.e. HTTPS instead of HTTP. The reason HTTP and FTP are not safe is that they are not...