"...He who has nothing to hide has already lost all."

"The ability to have secrets or, in other words, the awareness that there is a domain of inviolable intimacy, is what actually defines the individual. It is something that belongs to the core of our being, to our dignity. A sense of shame, of embarrassment, of not wanting to be observed that protects our identity. If we abandon this sense and say that you are allowed to see me naked, to photograph me and to read my mail, then we also abandon our personality, our pride, and even our identity. It is no longer possible to say 'I'; without secrets there is no 'I'. The self is lost."

German novelist Juli Zeh, Frankfurter Rundschau, Sept. 17, 2013
We are very concerned about the recent revelations on spying of the American NSA, the British GCHQ and other secret services into private communications of citizens. We are similarly concerned about abuse of private information for the purpose of advertising and behavioral tracking as done by companies such as Google, Yahoo or Facebook - especially if the authorities can access this information. We believe that such attempts potentially have a totalitarian core and endanger the democratic rights of citizens. The right of privacy is integral part of many national constitutions. However, these rights are not generally respected. Since governments do not protect us it is a duty of the individual to protect himself and others, and to make total surveillance more difficult.
Useful reading: Bruce Schneider, The Guardian, Sept. 6, 2013. -;- Electronic Frontier Foundation -;- The Guardian: NSA files decoded

Some hints on how to secure your privacy on the internet                                     (last updated Feb. 25, 2015)

There are some relatively easy things you can do to improve your privacy. Some of those are listed below (scroll page to see all).
Some further recommendations on how to make your computer more secure by using non-proprietary software can be found here: -->Prism-break.
Hide your IP address with TOR: Many websites track you with cookies. They use the unique IP (internet protocol) address of your computer in order to identify you. A new bad trick (2014) is Canvas fingerprinting (see it here in action). This technique identifies your computer even without the use of cookies. In order to prevent tracking of your internet searches and your general surfing habits, consider using the TOR browser instead of Chrome, Safari or other commercial browsers - especially by American companies that do not respect your privacy. The TOR browser is a derivative of Firefox and anonymizes your IP address. For this reason, you cannot be tracked any more. The TOR-browser also prevents Canvas fingerprinting. You find it here: TOR PROJECT. It takes somewhat longer to load a page, though. You can help the TOR project by optionally setting up a relay on your own computer.
Hide your IP address by using a virtual private network (VPN): VPN is another way to hide the IP address of your computer and to protect your privacy. VPN services typically cost some small fee. A very good Canadian provider is Tunnelbear. It costs about $5 per month. It exists for PC, Mac, iOS or Android. It works by tunneling you to a different server with new IP address in a country of your choice. A convenient legal side effect is that you may access some information and services in that country that are otherwise hidden to you.
Use long secure passwords: A very useful open-source tool that helps you to manage and to generate long passwords is KeePass (or KeePassX for Mac and Linux). Use different passwords for each purpose!
Write encrypted mails using asymmetric encryption: In order to do so, use mail clients on your computer rather than web mail. The most common and secure way is encryption with PGP (pretty good privacy). It is described here --> PGP Wiki. In order to send an encrypted mail, your mail partner needs to install PGP, too. There are secure public domain packets that can easily be installed on top of standard mail clients, e.g., Mac Mail (Apple, --> GPG TOOLS) or Microsoft Outlook (Windows, --> GPG4WIN). Alternatively, you can use the Thunderbird mail client and install the add-on ENIGMAIL on top of it (all platforms). Enigmail also uses the PGP encryption.
If you prefer using a browser window for writing mail (e.g., Gmail) then you can use an add-on for the Google Chrome and the Firefox browser called mailvelope. It does allow you to PGP-encrypt your mail within a browser window. PGP-encryption on an iPhone or iPad is possible with Apps such as oPenGP.
Use anonymized search engines: For companies such as Google, Yahoo, Microsoft, Facebook, etc., you are not a customer but your are part of their inventory. You are their product. These companies live on selling your data. Therefore, don't use Search Engines such as Google, Yahoo, Bing, ..., but rather DuckDuckGo. It is good, fast, and does not track you. There are also add-ons for Google Chrome and Firefox that anonymize your searches in standard search engines (--> disconnect.me). This is also good.
Browser Add-ons: Privacy Badger is an addon for the Firefox browser and Google Chrome recommended by the Electronic Frontier Foundation (EFF) that blocks spying adds and invisible trackers on webpages. https-everywhere/ is an addon for Firefox browser, Google Chrome and Opera by the EFF that encrypts your communications with many major websites, making your browsing more secure.
Chats/Messenger Apps: The commonly used app "WhatsApp" has now been sold to Facebook which is interested in the customer database. Further, there have been recurrent complaints about the security standards of this App. Secure alternatives with end-to-end encryption are Threema (a Swiss company), Telegram (Germany based) and Surespot. They exist for iOS, Android and other platforms.
Clouds: Cloud services offered by Google, Dropbox, ..., are subject to US legislation, which does not protect you. Further, not all of these services encrypt your data. There exist end-to-end encrypted alternatives, e.g., Tresorit (wikipedia). This is a Swiss cloud alternative with full encryption on your own computer before the data are uploaded. They offer the first 3 GB for free.
You can synchronize calendars and contacts between different devices (e.g., MacBook and iPad) with Fruux, which is a German based provider with much higher security standards than iCloud (Apple) or Dropbox. If you do not wish Apple and Co. to own all your contacts and calendar entries, try using secure alternatives!
TAILS: Secure operating system on a USB stick: Tails is a simple but secure operating system installed on a USB drive that can be used on all computers with Intel chips. It needs about 1 GB of space. You have to start your computer from the USB drive. The TOR browser is preinstalled. Mail connections are secure. No traces of your communications are left on your hard disk. Should work on PCs, and Macs with Intel chip (tested on a MacBook Air). Instructions for installation can be found on the Tails page.
Stop using Facebook, Google+ and similar networks: For various reasons, these Social Networks cannot be trusted - especially if they are located in the US or the UK. Your data are practically open to everybody. A description on how to delete your Facebook account can be found here:--> delete Facebook account. There are various other pages on the Web that teach you how to do it.
Stop autoloading images from html mails: Those images often contain code to read out a lot of information about your computer. It is instructive to check how much information you unwillingly distribute by going to this page: -->Email privacy tester. You might be shocked.
Use long secure passwords: A very useful open-source tool that helps you to manage and to generate long passwords is KeePass (or KeePassX for Mac and Linux). Use different passwords for each purpose!
Encrypt sensitive data: A good open-source tool for creating encrypted disks or encrypted directories is TrueCrypt. TrueCrypt is now maintained on a Swiss server (version 7.1). Don't use version 7.2 from the former site TrueCrypt.org. It is suspicious. On MacIntosh, the FileVault encryption (found in the security settings) encrypts your complete hard drive or external disks and USB sticks.
Smart Phones: Be very careful with the settings of the Apps. Smart phones permanently track you location. Many apps (such as Google Maps) collect data about your behavior. You can switch off the option to monitor your position in the system settings. Don't upload your contact list to apps.
Mail providers: Consider using mail providers that are located in countries with strict privacy laws, e.g., Germany. See here for some information: -->"E-mail made in Germany" initiative. A provider with very high security standards is Posteo. It does not ask for your data, and encrypts mail transmission. It charges 1 Euro per month.
Try convincing colleagues, friends and family about the need to protect their privacy.