I was using Ubuntu, but after updating to 14.04 LTS the Unity Desktop did not perform particularly well. So after research, I switched to Xubuntu, a recognised version of Ubuntu running the Xfce desktop environment.  Do both of these distros actually have anti-virus and anti-malware etc. built in, plus the programmable firewall, or are they just so called 'resistant' to viruses, because of supposed lack of Ubuntu specific viruses.   I have looked through many articles on Ask Ubuntu as well as other blogs, and all they seem to do is contradict.  Please help! Any help is greatly appreciated!
I am completely new in Ubuntu. Just installed Ubuntu 14.04. On my other computer running Windows, I am using Avast, free edition.  Do I need anti-virus protection at all?
Why doesn't an orbiting body keep accelerating? As a physics newbie I'm trying to get a grip on basic orbital mechanics. I think I'm beginning to get grasp on how bodies interact with each other. When a body approaches another body it accelerates due to gravity. It can reach a point where its velocity is high enough to keep falling but also keep missing the object it is falling towards. What keeps it from accelerating (because of gravity) and eventually reaching escape velocity? I feel like I'm either looking at things the wrong way or I have the entire thing wrong. In Chamber of Secrets, in the first Duelling Club class, Snape suggests Malfoy use the Serpensortia spell against Harry. This of course reveals that Harry is a Parselmouth, but how could Snape anticipate this? Was there any reason for Snape to suspect Harry is a Parselmouth? Or was it just a way to laugh at how Harry would get frightened? When are "if" and "whether" equivalent? What are the “spam” and “rude or abusive” (offensive) flags, and how do they work? find . -name *.rb   doesn't work on my ubuntu  I have to do  find . -name "*.rb"   to get it to work.  Why is that? I'm trying to understand Python's approach to variable scope. In this example, why is f() able to alter the value of x, as perceived within main(), but not the value of n?  def f(n, x):     n = 2     x.append(4)     print('In f():', n, x)  def main():     n = 1     x = [0,1,2,3]     print('Before:', n, x)     f(n, x)     print('After: ', n, x)  main()   Output:  Before: 1 [0, 1, 2, 3] In f(): 2 [0, 1, 2, 3, 4] After:  1 [0, 1, 2, 3, 4] limit of integral $n\int_{0}^{1} x^n f(x) \text{d}x$ as $n\rightarrow \infty$ I am trying to solve the following problem at the level of a senior undergrad analysis level. So, the problem is as follows: We are given a function $f$ which is continuous on the interval $\left [ 0,1 \right ]$, and the question is to find the limit: $$\lim_{n\rightarrow \infty}\int_{0}^{1}x^{n}f(x)dx\;.$$ The second part of the problem is to deduce the following limit: $$\lim_{n\rightarrow \infty}n\int_{0}^{1}x^{n}f(x)dx\;.$$  For the first part: I just did the following: For every $0\leq x&lt; 1$: $x\leq M$, where $0&lt; M&lt; 1$. Then: $$\int_{0}^{1}x^{n}f(x)dx\leq M^{n}\int_{0}^{1}f(x)dx\;.$$ Then: $$\lim_{n\rightarrow \infty }\int_{0}^{1}x^{n}f(x)dx\leq \lim_{n\rightarrow \infty }M^{n}\int_{0}^{1}f(x)dx= 0.\int_{0}^{1}f(x)dx=0\;,$$ so $$\lim_{n\rightarrow \infty }\int_{0}^{1}x^{n}f(x)dx=\lim_{n\rightarrow \infty }f(1)\int_{0}^{1}1dx=f(1)\;.$$ Does that make sense? If not, please show me the correct one.  As for the second part, I have no idea what to do. Any help? How to render Entity Reference fields in the current language I am trying to render fields from an entity reference in a twig template but they are displaying in the default language instead of the selected one. My twig code:  {% for location in node.field_locations %}   &lt;div class="home-location"&gt;     &lt;div class="wording"&gt;       {{ location.entity.title.value }}        &lt;span&gt;{{ location.entity.field_sub_title.value }}&lt;/span&gt;      &lt;/div&gt;    &lt;/div&gt;  {% endfor %} CSS overflow-x: visible; and overflow-y: hidden; causing scrollbar issue What does the explicit keyword mean in C++? What's the bad magic number error? What's the "Bad magic number" ImportError in python, and how do I fix it?  The only thing I can find online suggests this is caused by compiling a .py -> .pyc file and then trying to use it with the wrong version of python. In my case, however, the file seems to import fine some times but not others, and I'm not sure why.  The information python's providing in the traceback isn't particularly helpful (which is why I was asking here...), but here it is in case it helps:  Traceback (most recent call last):   File "run.py", line 7, in &lt;module&gt;     from Normalization import Normalizer How to get Url Hash (#) from server side Pigeonhole Principle Question - Group of 6 people, do 3 either know each other or not? Prove that in any group of 6 people there are always at least 3 people who either all know one-another or all are strangers to one-another.  Hint: Use the pigeonhole principle.  I don't see how this applies to the pigeonhole principle because I keep imagining a group of 4 strangers, and then 2 friends. This would be 6 total but against what the proof is asking. Maybe I don't understand the proof in question... Why is glass transparent? Once I asked this question from my teacher and he replied "Because it passes light.". "And why does it pass light?" I asked and he said, "Because it is transparent.".  The same question again, Why glass is transparent? Why does light pass through it, while for opaque objects, it does not? What exactly do the colors in htop status bars mean? How to acknowledge a deceased advisor’s contributions to a paper? One of my advisors suddenly passed away while I was in graduate school.  We had some discussions and ideas about future publications, but he passed away before any of the work was completed.  When the work was finally completed and published, I and my co-authors were therefore presented with an ethical dilemma about how best to acknowledge his contributions to the ideas behind the paper.  Should we list him as a co-author?  Put him in the acknowledgements?  Listing him as an author would give credit for the original idea, however, we would have no way of knowing if he actually approved of—and would want his name attached to—our methods and writing.  In the end my co-authors and I decided to list him as a co-author with a footnote stating that he passed away before publication.  I’m interested to hear from others who have been in similar situations and/or suggestions on what constitutes “co-authorship” when one of one’s collaborators passes away before the publication or work is complete. How to burn or mount an ISO file? This is something I've been curious about since starting this whole 'meta' thing a couple years back.     Let's say a user posts a feature request.   Under what circumstances is the feature-request read by staff? If staff decline to do anything (I'd guess it's some sort of triage), under what circumstances is the feature-request reevaluated by staff?     Let's say a user posts a bug.    Under what circumstances is the bug tested? What generally determines whether a verified bug is actionable? (And/or what are the criterion for deciding what to do?)     For both of the above, would it be possible to see a general-but-relatively-detailed flow for what happens to these questions? After upgrading my laptop from karmic to lucid, my fat32 partition won't mount automatically. I get the message:  The disk drive for /osshare is not ready yet or not present Continue to wait; or Press S to skip mounting or M for manual recovery   Funny thing is, if I skip, then /osshare/ is mounted once I log in.   I've a similar setup on my desktop, and it works fine. Fstab on desktop:  UUID=4663-6853  /osshare        vfat    utf8,umask=007,gid=46 0       1   /etc/fstab on laptop:  UUID=1234-5678 /osshare vfat utf8,auto,rw,user 0 0 How to delete empty folder with thumbs.db without disabling thumbnails I often have problem to delete a folder that contains a thumbs.db file. Also tools like  fail. It seems to be loccked by os for some unknown reason. The only solution i found in the net was to disabling thumbnails in windows but this is a bad workaround isn't it?  Is there a "normal"(or official, supported by MS) way to delete an empty folder that only contains a thumbs.db?