Ask Leo! #680 – Where Do Cookies Come From?

This Week

It only sounds like it's related to Thanksgiving, but it's not: where cookies come from. (It's not the kitchen.)

That random wireless network that you can connect to?. Don't.

And, a novel use for One Note.

TEH Podcast

Nope, that's not a typo - the Tech Entusiast Hour is a new weekly podcast, and I'm one of the four "semi-regular" hosts. Each week we discuss the news of the day, highlight what's exciting, and maybe even rant a little from time to time. You know, because we have opinions. :-)

The Tech Enthusiast Hour is available in iTunes, as well as other popular podcatchers and podcast players. The website also includes shownotes, as well as an embedded audio player so you don't need to do the whole "podcast" thing unless you really want to.

Speaking of Thanksgiving

I'm thankful for you! Thank you for being here, and thank you for supporting what I do. I'm honored.



Where Do Cookies Come From?


I have cookies on my computer from websites that no one in my household said they had visited. Is this possible? Is there a way to tell if a cookie was an actual site visited or a third-party cookie?

Yes, it's very possible to find cookies from websites you've never been to. In fact, I'd say it's almost a certainty.

However, I can't think of a way of telling third-party cookies apart from those sites you actually visited.

It gets surprisingly complex.

Let's look at where cookies come from.

The sites you visit

The most obvious source of cookies are those created when you visit a website.

That makes sense, and it's probably what most folks immediately think of when they hear that a site uses cookies.

Ask Leo! is a fine example. The site uses cookies for a variety of things, the simplest being to remember whether or not you've seen the newsletter offer pop-up.

Resources used by the sites you visit

A less-obvious way to accumulate cookies is from sites that pull resources from more than one web server.

For example, a site like might create and leave cookies under its own name, as above.

However, might load its images from another web site entirely — say, If also uses cookies, it now has the opportunity to place a cookie associated with its domain on your machine.

That's one source of unexpected cookies: when you visit, you get cookies for, but you also get cookies for

That's a third-party cookie. You're the first party, the site you visit is the second party, and any additional sites involved are third parties.

Advertisers on the sites you visit

This is what most people think of when they think of third-party cookies.

Much like the image resources I just talked about, ads are also typically served up from another server. That server, too, has an opportunity to leave cookies on your machine.

Once again, Ask Leo! is a fine example. I have advertising on this site provided by Google's AdSense service. As a result, you may find cookies produced from a variety of domains ( being one example) Google uses to provide those ads.

If you have third-party cookies enabled in your browser settings, you can expect to find cookies from advertising sites.

Cookies from pop-ups

Many people block or hide pop-up windows. Even if you do, cookies can still result from them.

I know that this sounds a little odd, but the net effect is that a cookie gets left for a web page you never see.

It depends on how your browser detects pop-ups, what kind of pop-up technology is being used, how quickly they're detected, and exactly how they're blocked, closed, or hidden.

In some cases, the pop-up can exist long enough to leave a cookie on your machine.

Cookies from sites you haven't been to … yet

This might be the oddest of all.

Some web browsers pre-fetch pages that are linked on the current page you're viewing.

For example, this page has links to other Ask Leo! articles. Once your browser has completed displaying this page, it may decide to go and fetch those other pages, just in case you decide to go to one of them.

Why? In a word, speed. If you do click one of those links, the page will come up faster, having already been downloaded.

Now, the question is: if there are links to other sites on a page you're viewing, does pre-loading those sites also allow them to leave cookies? My belief is that that answer is: maybe. It depends on the site, the browser, and a number of other technical details.

But if that happens, you'll find cookies for sites you might never have visited.

Related Links & Comments: Where Do Cookies Come From?

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Is it OK to Use this Random Wireless Network I Just Found?

My internet connection went down on a Friday, and the service rep gave me a service call time for Monday, maybe. My HP notebook has wireless capability so I turned it on and checked what wireless networks were available. There are 3 secured and 1 unsecured wireless networks. I am able to logon to the unsecured wireless network, a NETGEAR network. The signal is low and only about 500K but works. Am I breaking the law by using someone else's wireless network? Is there a way to find out where this wireless network is and who owns it, hopefully it is a free public wireless network? Am I in any danger from using this wireless network? I am not doing anything that requires a password, and I have Windows Firewall, Norton antivirus, and Windows Defender running on my computer.

What you're doing is very common. With so many open wireless hotspots around, it's a temptation that's frequently too hard to resist, particularly when you're in need.

Yet resist it you should.

There are a number of problems that arise from connecting to an unknown but open hotspot.

Continue Reading: Is it OK to Use this Random Wireless Network I Just Found?

Use OneNote for Basic OCR

OCR, an acronym for Optical Character Recognition, is a process that converts a picture of text into actual, editable, text.

For example, you might find a picture of a meme on social media, which may be nothing more than text on a nice background saved in an image format, such as .jpg. Or you might scan a document you've received, which often results in a series of image files, or a PDF containing a series of images — “pictures”, if you will, of the individual pages.

Rather than retyping that text by hand to use elsewhere, you can use OCR to automatically extract the text for you.

As it turns out, Microsoft OneNote, present in Windows 10 and Microsoft Office, has basic OCR capability built in.

Continue Reading: Use OneNote for Basic OCR

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Posted: November 28, 2017 in: 2017
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