I love to take photos of people in urban areas; buildings, houses, cars, motion, expression... everything. However, taking photos of people and taking photos of indoors without having any permission, might not be morally correct?   Taking a photo of another human being without his or her permission - is this ok? Taking photos of interiors (like a pub, not a house) through the windows - is this ok? Taking photos of street performers without permission of the actors - is this ok? Taking a photo of a painting that an artist is selling on the street - is this ok? Taking photos of random kids - correct or not?   From my point of view, I am not doing any harm, just looking for beauty; probably 3/4 of my photos will be deleted anyway. But I do understand that people do not feel ok to be photographed by someone. I try to ask, but you can't do that all the time; many times it is just a spontaneous moment...  Is there any 'law' I should be aware of?  EDIT  I want to only publish photos on e.g. 500px, not to sell or anything, just to share them as something I find nice.  Unfortunately, I live in the country where these rules are old and everything is regulated by the statement that photo must not disturb the privacy of the subject. But than shooting two people sitting on the bench is not legal. Etc.
If one were to take a similar path as  in shooting candid street photography today, should they be concerned about laws or other realistic norms of today? I am wondering specifically in the US speaking broadly of all states. I am not looking for legal advice, but anything that one photographer to another would caution against as potentially being grey or obviously illegal.  Similar previous question:
How to set default style for arrow tips in TikZ? I read a book that answers one of my questions, and I would like to quote it as an answer. Is that illegal?    Thanks. Why does the degree of freedom of SSR equals 1 in simple linear regression What do you call the grouping of numbers based on the cardinality of digits in the square they produce? Clear 301-redirect cache in Firefox Is it possible to clear only 301-redirects from Firefox's cache? CTRL+F5 doesn't do the job since you just reload the target without caching but do not clear the cached redirect.  An option to disable caching of those redirects completely would be fine, too - but some way (possibly through an extension) to remove those cached redirects would be better.  Note: I'm not looking for answers that disable all caching (including CSS, JS, etc.) I can type:  dirname ~/home/blah/file.zip   for instance, and this works fine alone, but when I use this syntax as the parameter for some command it always reads 'dirname' as the desired directory. i.e.:  cd dirname ~/home/blah/file.zip bash: cd: dirname: No such file or directory   Basically, how do I get 'dirname file' to be read as one entity? Short story with competitors complaining to government about a new very popular synthetic food I'm trying to fix the following TikZ figure, where the circle device in the middle should be embraced by two bended arrows pointing counter-clockwise.    I have drawn these arrows with an arc path, but the tips of the arrows are unexpectedly both pointing upward.  Any idea how to get these arrow tips to follow the direction of the arc?  Here is my code for the above figure:  \documentclass[12pt]{article}  \usepackage{tikz} \usetikzlibrary{arrows} \usetikzlibrary{calc}  \begin{document} \begin{tikzpicture}   \draw (0,0) circle (1cm);   \draw[fill=gray!20]  (23:0.45cm)     -- (23:1cm) arc[radius=1, start angle=23, end angle=-203] (157:1cm)     -- (157:0.45cm) arc[radius=0.45, start angle=157, end angle=23] (23:0.45cm);   \draw[fill] (0,0) circle(2pt);   \draw[-&gt;,&gt;=stealth',semithick] (150:1.2cm) arc[radius=1.2, start angle=150, end angle=210] (210:1.2cm);  \draw[-&gt;,&gt;=stealth',semithick] (-30:1.2cm) arc[radius=1.2, start angle=-30, end angle=30] (30:1.2cm);   \foreach \x/\y in {1/0,2/0,3/0,4/1,5/1,6/1,7/0,0/1}     \node[rotate={\x*45-90}] at ($(0,0)!.75!\x*45:(1,0)$) {\y} ; \end{tikzpicture} \end{document} is a wonderful freeware Windows swiss-army-knife for image viewing &amp; editing.  For me, the key features are fast viewing, simple editing (crop, contrast, brigthness, rotation, resampling), file operations (delete, copy to folder) and extended image information access (exif data) combined in the same interface. Versatile batch jobs are a very nice bonus.  But unfortunately IrfanView is for Windows only, and isn't . What would be the nearest equivalent for linux? Every infinite subset of a countable set is countable. Here is the proof I tried to weave while trying to prove this theorem:     Theorem. Every infinite subset of a countable set is countable.      Proof. Let $A$ be a countable set and $E\subset A$ be infinite. Then $A\thicksim\mathbb{N}$. This implies that there is a sequence $\left\{x_{n}\right\}_{n\in\mathbb{N}}$ where $x_{n}\in A$. Construct a sequence $\left\{n_{k}\right\}_{k\in\mathbb{N}}$ where $x_{n_{k}}\in A$, $n_{1}$ is the smallest positive integer such that $x_{n_{1}}\in A$, and $n_{k+1}&gt;n_{k}$. 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For instance where is Firefox or Libre Office (that are installed by default)?  Got this question when I was trying to install eclipse. Downloaded the zip, and was wondering... I don't need a recommendation or a list but my knowledge of GPS and "navi"s and the differences between them is an utter mystery to me.  But often I'm lost in backstreets in random countries where access to something like a live Google Maps would be awesome. I absolutely cannot afford a smartphone with worldwide roaming though.  Can GPS's do what I want or am I barking up the wrong tree? If they can is it only high end ones than can? Iterated self-composition of arbitrary function Does there exist some notation that represents the iterative composition of a single-input, single-output function with itself? As in, say, $f_5(x)=f(f(f(f(f(x)))))$.  In other words, going by the above (incorrect, I'm pretty sure) notation:  $f(x)=x+1$, $f_n(m)=m+n$  I'm looking for the correct way to express the notion of "$f_n(x)$" for any $f$. Simulation of interacting particles I have been reading through the  and was curious about the  declaration. I personally have never used it, however I am interested in exploring the language.   What is a good example of using friend?    Reading the FAQ a bit longer I like the idea of the &lt;&lt; &gt;&gt; operator overloading and adding as a friend of those classes. However I am not sure how this doesn't break encapsulation. When can these exceptions stay within the strictness that is OOP? "Open in terminal" not working on nautilus as root When using natilus as root, open in terminal used to work as using with any user. However, when I press open in terminal when using nautilus as root now, it does nothing.  How to solve it?  The error:  GLib-GObject-CRITICAL **: g_object_set_data: assertion 'G_IS_OBJECT (object)' failed Does there exist a surjective homomorphism from $(\mathbb R,+)$ to $(\mathbb Q,+)$ ? Does there exist a surjective homomorphism from $(\mathbb R,+)$ to $(\mathbb Q,+)$ ?  ( I know that there 'is' a   'surjection' , but I don't know whether any surjective homomrophism from $\mathbb R$ to $\mathbb Q$ exist or not . Please help . Thanks in advance ) How do you return from 'gf' in Vim I am using Vim for windows installed in Unix mode. Thanks to this site I now use the gf command to go to a file under the cursor.  I'm looking for a command to either:   return to the previous file (similar to Ctrl+T for ctags), or   remap gf to automatically launch the new file in a new window. Why does my wife's skin buzz when she's using her laptop?