TL;DR: Your computer is sending my server data. I promise I won’t abuse that data, but I can’t promise that 3rd parties won’t.
I am running a self hosted version of Piwik, a web analytics software. Piwik should set a couple of cookies with names like _pk_*. So far I’ve identified two cookies from Piwik: _pk_id.* which is set for ~1 year and seems to be used to identify if you’re a returning visitor or not, and _pk_ses.* which is set for 30 minutes and seems to be used to track what you’re doing during a session.
I’m just getting to know Piwik, but I have already replaced Google Analytics with it. I am hosting it myself, and I am the only one with access to the data. The purpose of the data harvest is absolutely not to identify any single individual, but to gather generalized statistics on how my web site is being used.
Piwik came with this setting enabled, and I left it there:
I am using the free GeoIP country database from Maxmind with the anonymized IPs, and from what I can tell, this is not even good enough to track what country you are visiting from.
As far as I know, no tracking data is sent from my self-hosted Piwik to any 3rd party.
If you sign up for my newsletter, I will of course have access to the data you sent along with some other data you may or may not know that your computer sent. Including, but limited to, your IP address, user agent and more stuff. I will not use this information you trusted me with, for anything I consider immoral or evil (my standards might be different than yours, but I’m not trying to fool you into anything. If you just signed up for updates from this web site, that’s all I’m going to send you).
I’m trying my best to not disclose the info with anyone else, but I’m sending the newsletter through SendGrid, I guess they are doing some logging on their side. Anything else would be stupid of them. I didn’t bother reading their privacy statement, but I’m guessing it’s OK.
I am sharing some anonymized data with MailPoet, who provides the newsletter functionality that I am using. More info on the data they are gathering is available here.
Here’s a bad part: The newsletter plugin I am using, MailPoet, tracks opens and clicks. Not only counting, but privacy violating info on who does what and when. I have not yet figured out how I can turn this off. This data is not sent to a 3rd party, so I’m the only one with access to it. For better privacy, you can use my RSS feed instead.
If you choose to leave a comment on a post, I will in addition to the info you provide, store the time and date of your submission and your IP address. I don’t really use your IP address for anything, it’s just how the commenting system works in WordPress.
A final warning
Just let it be clear that I probably can harvest some behavioral and identifying information about you, but I have no intention of doing so. If I did, I would be a much lesser human being than I’m aiming for.