The internet is inherently insecure. Whenever you send data across it, there is a chance that that data could be sniffed, and someone could end up with your personal data. Hopefully once you've read this article, you'll have a better understanding of how to prevent this from happening.
When data travels through the internet, it needs to pass through multiple connections to get to its final destination. Most people don't realise that the data can be read by any machine it passes through on this journey.

With the right tools, you can sniff this data yourself, and any data that passes through your network. This is because most networks actually send data intended for anyone on that network to all machines on your network, and your computer will ignore anything that's not meant for it. This is especially true for most wireless networks, even networks that are 'secured' with WEP/WPA.

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