most of the apps have their executables in /usr/bin and other files also in the generally defines folders..  But i found some apps keep their executeables elsewhere...Now as in linux any file can be executeable the file can actually be placed anywhere..  But for achieving proper segrigation and stuff which locations  have been defined as the ones that should be preferably be used for various files of an app?  Is there any specification for it as such?
In Windows there’re perhaps only a couple of important folders (by important I mean important in my logical picture of the Windows file system) in the installation drive (in my case C:\). Namely Program Files and Windows. I simply stay away from Windows folder and the “add remove program files” is good enough to handle the program files folder of Windows. Of course there’s a folder named Users where the users (who are not admins) can access only their folders.  Thus there’s a clear picture at some level in my mind of the Windows file system. In Ubuntu, when I reach the location /, there’s a huge list of folders, most of which I have no clue as to what they contain. The /bin folder seems to be the equivalent of the Windows folder in windows. The /usr folder seems like it’s the equivalent of the Users folder in Windows. But even the /home folder looks like it can fit the bill.  Please understand that I do understand, that Ubuntu (Linux) has a different character than that of Windows, i.e., there need not be exact equivalent of Windows functions, in Ubuntu. All I am looking for is a bit more clearer picture of the Ubuntu file system.   This question is a part of a bigger question which I am splitting up to make it more answerable. The original question can be found here:
Is there a rule of integration that corresponds to the quotient rule? Where is it preferred to place the answer to duplicate questions? The trigonometric ratios of an angle greater than $90^\circ$ are equal to the supplementary angle's ratios.  I'm just clarifying this, but the ratios don't actually exist for angles greater than $90^\circ$ right? (since by definition these ratios are of a right angle triangle). Is it just mathematical custom to assume the ratios of an angle greater than $90^\circ$ to be equivalent to its supplementary angle's ratios? For convenience? SQL comma-separated row with Group By clause What is the effect of having correlated predictors in a multiple regression model? I learned in my linear models class that if two predictors are correlated and both are included in a model, one will be insignificant. For example, assume the size of a house and the number of bedrooms are correlated. When predicting the cost of a house using these two predictors, one of them can be dropped because they are both providing a lot of the same information. Intuitively, this makes sense, but I have a some more technical questions:   How does this effect manifest itself in p-values of the regression coefficients when including only one or including both predictors in the model? How does the variance of the regression coefficients get affected by including both predictors in the model or just having one? How do I know which predictor the model will choose to be less significant? How does including only one or including both predictors change the value/variance of my forecasted cost? Added activities, now names and labels and strings aren't registering Android Manifest file What are the biggest changes between UA Ranger and PHB Ranger? How to backup an Android device? How do I rename a directory via the command line? I would like to remove my Raspberry Pi from my iPhone 8 (running iOS 11.2.1) as a connected bluetooth device.  Normally, I would go into my Settings -> Bluetooth and select the Info button (a small blue circled "i") to show the "Disconnect" and "Forget Device" dialogs:    Unfortunately, iOS does not give me this option for my device. The bluetooth device list does not contain an "i" for the item, and there is seemingly no other way to disconnect.    How do I unpair this device if there is no button to trigger to the unpair prompt?  Due to work restrictions I cannot completely reset the device. Do I need to have antivirus software installed? I thought that there was no need to scan for viruses either in Ubuntu or any Linux distros until I found virus scanner packages clamtk and klamav in Ubuntu software center yesterday.  This leads to the following questions:   How do viruses differ between Linux and Windows? How do the strategies for protection differ between Linux and Windows? Should a virus scanner package be installed on my system? If so, which would be a better option? Legality of using names in a game? I had this question:    All 3 responses were rated at 1 when the bounty expired. Nothing got selected as the "best answer", and I can't even manually select an answer. Generate random numbers uniformly over an entire range Is the following proof correct, or are certain steps illegal?  Suppose $f:G_1\to G_2$ is a surjective group isomorphism, $N_1\lhd G_1, N_2\lhd G_2$ normal subgroups, with $N_1=f^{-1}(N_2)$. Prove that $(G_1/N_1)\cong (G_2/N_2)$.  Proof:  As $f$ is surjective, we an use the first isomorphism theorem to get $G_1/\ker(f)\cong G_2$, which implies that $$(G_1/\ker f)/(N_1/\ker f)\cong G_2/(N_1/\ker f)$$  Using the first isomorphism theorem we also know that $$N_1/\ker (f)\cong f(N_1)=f(f^{-1}(N_2))=N_2$$  Combining this we can see that $(G_1/\ker f)/(N_1/\ker f)\cong G_2/(N_1/\ker f)\cong G_2/N_2$.  Using the third isomorphism theorem we have that: $$ (G_1/\ker f)/(N_1/\ker f)\cong G_1/N_1$$  And from the last two lines we have $G_1/N_1\cong G_2/N_2$ $\tag*{$\Box$}$ Memory management in Objective-C MikTex 2.9 Installation Error: File name database capacity exceeded. Excel VBA code to turn a row with a variable number of columns into fixed-length rows I would like to change this:  Filer   ShareName       IPAddress1    IPpaddres2    IPAddress2    ... ... .... ServerA /share1/tools   192.168.1.52  192.168.1.65  192.168.1.158 ServerA /share/library  192.168.1.65  192.168.1.61  192.168.1.155 ServerB /share/tools    192.168.1.158 192.168.1.159 ServerD /share/misc     192.168.1.7 .. ... ..... .......   To this, in a new worksheet:  Filer   ShareName       IPAddress ServerA /share1/tools   192.168.1.52 ServerA /share1/tools   192.168.1.65 ServerA /share1/tools   192.168.1.158 ServerA /share/library  192.168.1.65  ServerA /share/library  192.168.1.61  ServerA /share/library  192.168.1.155 ServerB ... ... ServerD ... ... .. ... ..... ....... How to change an application icon programmatically in Android? Allow Documentation in other Stack Exchange communities I'm a Salesforce developer and would love Documentation to be available in other Stack Exchange communities. The reason is  a lot of Salesforce developers get help, especially newer ones like myself. The developer forums and documentation on  is mediocre. It would be nice to allow users to create their own and give pack on