Social networking sites encourage people to be more public about their personal lives. Because intimate details of our lives can be posted so easily, users are prone to bypass the filters they might normally employ when talking about their private lives. What's more, the things they post remain available indefinitely. While at one moment a photo of friends doing shots at a party may seem harmless, the image may appear less attractive in the context of an employer doing a background check. While most sites allow their users to control who sees the things they've posted, such limitations are often forgotten, can be difficult to control or don't work as well as advertised.
Paper coffee filters were invented in Germany by Melitta Bentz in 1908  and are commonly used for drip brew all over the world. In 1954 the Wigomat , invented by Gottlob Widmann , was patented in Germany being the first electrical drip brewer.  Drip brew coffee makers replaced the coffee percolator in the 1970s due to the percolators' tendency to over-extract coffee, thereby making it bitter.  One benefit of paper filters is that the used grounds and the filter may be disposed of together, without a need to clean the filter. Permanent filters are now also common, made of thin perforated metal sheets or fine plastic mesh that restrain the grounds but allow the coffee to pass, thus eliminating the need to have to purchase separate filters which sometimes cannot be found in some parts of the world. These add to the maintenance of the machine, but reduce overall cost and produce less waste.