
Ask HN: How could YouTube know about friend's heart attack? - throwawayB1937
Friend of mine&#x27;s dad has a heart condition. Happened in the past 2 months. Only speak through text about it. Never looked it up because I don&#x27;t know the exact details. Got a few more details through a Slack conversation the other day.<p>Freaked out because YouTube just played an ad about a heart failure medication after a video. This has never been relevant my entire life until this year. I&#x27;ve watched a lot of YouTube. I&#x27;m really freaked by the timing. My Facebook age is 95, but nothing like this has ever played before.<p>Seriously considering online privacy options.
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watmough
Ok, so quite interesting to look at how all this works:

Top of this page: [https://slack.com/privacy-
policy](https://slack.com/privacy-policy)

Information we collect and receive 1\. Customer Data

Content and information submitted by users to the Services is referred to in
this policy as “Customer Data.” As further explained below, Customer Data is
controlled by the organization or other third party that created the team (the
“Customer”). Where Slack collects or processes Customer Data, it does so on
behalf of the Customer. Here are some examples of Customer Data (but keep in
mind they are only examples and there may be others): messages (including
those in channels and direct messages), pictures, videos, edits to messages or
deleted messages, and other types of files. A user may also choose to enter
information into their profile, such as first and last name, job, a photo and
a phone number.

And somewhat lower down:

Sharing and Disclosure There are times when information described in this
privacy policy may be shared by Slack. This section discusses only how Slack
may share such information. Customers determine their own policies for the
sharing and disclosure of Customer Data. Slack does not control how Customers
or their third parties choose to share or disclose Customer Data.

1\. Customer Data

Slack may share Customer Data in accordance with our agreement with the
Customer and the Customer’s instructions, including:

With third party service providers and agents. We may engage third party
companies or individuals to process Customer Data. With affiliates. We may
engage affiliates in our corporate group to process Customer Data. With third
party integrations. Slack may, acting on our Customer’s behalf, share Customer
Data with the provider of an integration added by Customer. Slack is not
responsible for how the provider of an integration may collect, use, and share
Customer Data.

In short, it pretty much looks like they can do what the heck they want with
anything you type in.

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wayn3
doesnt mean that slack shared his data. if you use slack through chrome,
google has your slack data and youtube is part of google.

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jbms
It could be coincidence where the situation happening and being discussed
keeps it in your consciousness and caused you to notice the advert.

If the ad played 2 months and 1 day ago would you be freaked out that YouTube
predicted the future? You may have ignored it and not made a connection.

Simple evidence for this - note the large % of Youtube Ads that are totally
irrelevant to you.

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cm2012
Google knows who your friends are, they probably gave off a lot of signals.
Also maybe similar ip or geolocation.

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spooky123
Google is basically Santa Clause.

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spooky123
2spooky4me.

They're listening. All these apps and websites are.

