The basic tenet of Safari private browsing is that it alters the way your browser operates. Private browsing is called different names in different browsers, so depending on what you're using, you'll either see Incognito Mode in Google Chrome, InPrivate Browsing in Internet Explorer, and other similar terms in Opera, Mozilla etc.
Browsing normally in Safari
When you browse the web normally Safari web browser saves your history – i.e. the websites that you've visited, cookies and the data they've collected from sites you visit, passwords you've saved, and any files you have downloaded.
What this means is that anyone logging on to your computer can simply access your browser and see all of this information. What's more, they won't need to access your history either. Just by typing a search term into a search engine or a website URL into your address bar, Safari will helpfully bring up the list of sites or keywords that you've previously been looking for. Of course, like most aspects of your computer's operating system you could disable some of these tools, but how many of us even think about doing that in advance?
Browsing privately in Safari
So, as we've seen, if you are using the internet in 'normal mode' your web browser will be storing your search history and any related data and downloads. Switch on private browsing mode and none of this information will be collected – apart from cookies, which will usually be stored while you are online, however these should be deleted as soon as you close the browser.
So far so good, but one thing you do need to be aware of is that when you're using Safari's private browsing mode it will only be activated on the websites that you consciously use it for. If you have three tabs open with a different website open in each, just because you have activated private browsing mode in the first tab, don't think that the remaining two websites will be incognito too as they won't be. For 100% private browsing (as much as it can be said to be private), you have to turn on private mode separately for all of the sites you are looking at.
Other privacy issues with private browsing mode
Okay, so we know that Safari is not able to monitor you when you're online if you have private browsing mode activated but what about other applications? If you're unfortunate enough to have a malware infection – such as spyware or a keylogger – then there is absolutely nothing to stop them from spying on you. Private browsing mode won't stop anyone – from malicious third parties to parents using parental control software to companies that monitor employee web usage - from seeing what you’re up to online.
Another thing you need to be aware of if you're thinking that private browsing has your back is that although your browser will be prevented from saving your history on your PC, that doesn't mean that other parties are subject to the same restrictions. Put simply, it will work for you, but not for other parties.
External computers, routers and servers that are all connected to your computer will still be able to see your activity, IP address and location – no matter whether private mode is on or not. Let's take this as an example: you've turned on private mode and settled down for an enjoyable afternoon spent uploading your vacation pictures to Facebook – while using your employer's or school's network. This activity might go undetected by your computer but your usage is still easily accessible on your business's or institute's routers. Safari Private mode also doesn't conceal your IP address either, so servers will still know your physical location. That's not to say you can't hide your IP address – you can by using a VPN for example – but private browsing won't do that for you.
Looking at websites of a dubious nature in the comfort and privacy of your own home? Well don't think that private browsing will save you here either as all search requests are still being routed through your Internet Service Provider, eventually ending up on their servers.
Private browsing mode might sound like a dream come true for anyone who wants to hide their searches – for pure reasons or foul, or for those who are hoping their boss or teacher won't notice if they're slacking off, but it's not quite the foolproof safety net many people assume it is. Yes, it can conceal your browsing history from anyone using your computer but that doesn't mean it won't be logged in multiple other places. And if you really want to browse the Internet in anonymity you need a VPN as this will go one step further than private mode and hide your IP address - from everyone. It also encrypts data and traffic meaning that if you really don't want anyone to know which sites you visit, it's your only option.