How do I make my home or small business Wi-Fi network safe?

To make your home or small business Wi-Fi network safe, the single most important thing to do is implement the authentication security capabilities built into your Access Point and Wi-Fi adapters.  Authentication lets you control who can access your wireless network, and encrypts (scrambles) your wireless network data transfers so no one can eavesdrop on you.  First set up the Access Point by connecting it with a network cable to your PC, then using a browser to set up the security.  Check your manual for detailed instructions.  You will be setting up your network password, so be sure to write down and keep it somewhere you can find it.  You then need to setup all of your wireless PCs with the matching security and passwords so they can use the network.  Usually you can do this by clicking the little antenna in the lower right of your desktop, and then following the guided setup process.  Use the newer Wi-Fi Protected Access (WPA) encryption.  It shows up as either WPA-Personal or WPS-PSK (for Pre-Shared Key) on your setup screens.  They are the same.  The newest security on the scene is WPA2.  Avoid using the older Wired Equivalency Privacy (WEP), because it can be easily broken in a few minutes with widely available tools.  One note is that all the devices on your network have to have the same security, so if you have some older devices that don’t support WPA, you should replace them.