Nowadays i'm getting too much of spam emails from my contact form, below is it's html view,      &lt;form id="contactForm" action="processform.php" method="post" class="positioned" style="display: inline;"&gt;         &lt;ul&gt;             &lt;li&gt;                 &lt;label id="textname"&gt;Name :&lt;/label&gt;                 &lt;input type="text" name="senderName" id="senderName" placeholder="Type your name" required="required" maxlength="200"&gt;             &lt;/li&gt;     &lt;li&gt;                 &lt;label id="textemail"&gt;Email :&lt;/label&gt;                 &lt;input type="text" name="senderEmail" id="senderEmail" placeholder="Type your email" required="required" maxlength="200"&gt;             &lt;/li&gt; &lt;li&gt;             &lt;label id="textmessage" for="senderfeedback"&gt;Feedback :&lt;/label&gt;             &lt;input type="textarea" name="senderfeedback" id="senderfeedback" placeholder="Type your Message here" required="required"&gt;         &lt;/li&gt;     &lt;li&gt;                 &lt;label&gt;&lt;/label&gt;                 &lt;input type="submit" id="sendMessage" name="sendMessage" class="button" value="Submit"&gt;             &lt;/li&gt;        &lt;/ul&gt;         &lt;/form&gt;   I think some auto bot is accessing my processform.php file. Is there any way to stop this ?
It looks like we'll be adding  support to Stack Overflow. This is necessary to prevent bots, spammers, and other malicious scripted activity. We only want human beings to post or edit things here!  We'll be using a JavaScript (jQuery) CAPTCHA as a first line of defense:    The advantage of this approach is that, for most people, the CAPTCHA won't ever be visible!  However, for people with JavaScript disabled, we still need a fallback and this is where it gets tricky.  I have written a  which we can re-use.    However, I'd prefer to go with something textual to avoid the overhead of creating all these images on the server with each request.  I've seen things like..   ASCII text captcha: \/\/(_)\/\/ math puzzles: what is 7 minus 3 times 2? trivia questions: what tastes better, a toad or a popsicle?   Maybe I'm just tilting at windmills here, but I'd like to have a less resource intensive, non-image based &lt;noscript&gt; compatible CAPTCHA if possible.  Ideas?
Skype window problem in Ubuntu 14.04 Reflection of sound waves from the open end of an organ pipe & relationship b/w nodes & pressure We know that standing waves are created when any wave traveling along the medium will reflect back when they reach the end. But in an open organ pipe, there is nothing to oppose the wave and reflect it back. So then how are standing waves created in such a case? In standing waves where is the pressure greater, at nodes or anti-nodes? I want to resolve merge conflicts in my Git repository. How to do that ? Quad tree vs Grid based collision detection How do I enable the "Universe" repository? How do I get to the Universe Repository in supported versions of Ubuntu? Existence in ZF of a set with countable power set Methods to compute $\sum_{k=1}^nk^p$ without Faulhaber's formula As far as every question I've seen concerning "what is $\sum_{k=1}^nk^p$" is always answered with "Faulhaber's formula" and that is just about the only answer.  In an attempt to make more interesting answers, I ask that this question concern the problem of "Methods to compute $\sum_{k=1}^nk^p$ without Faulhaber's formula for fixed $p\in\mathbb N$".  I've even checked this  without finding what I want.  Rule #1: Any method to compute the sum in question for arbitrary $p$ is good, either recursively or in some manner that is not in itself a closed form solution.  Even algorithms will suffice.  Rule #2: I don't want answers confined to "only some values of $p$".  (A good challenge I have on the side is a generalized geometric proof, as that I have not yet seen)  Exception: If your answer does not generalize to arbitrary $p$, but it still generalizes to an infinite amount of special $p$'s, that is acceptable.  Preferably, the method is to be easily applied, unique, and interesting.  To start us off, I have given my answer below and I hope you all enjoy. How do I check if a file exists in Java? Should I always use a comma before a quote? Install on usb external hard drive I am new to ubuntu and i would like some help. I have a laptop with windows 7 installed but i would love to have ubuntu too because it's a great OS. So i would like to install ubuntu on an external usb hard drive (320 - 500 GB) and i have some questions about that :   Do i need a usb external hard drive which will be compatible with ubuntu - linux ? or i can do it with any hard drive  If i make a partition on it for ubuntu staff will i be able to use it and save other staff in the usb hard drive (movies,songs,documents etc) ? If i have ubuntu installed on the usb hard drive will i be able to boot ubuntu from any pc ? Are my changes going to be saved normally or my settings will be lost after shut down ?   Waiting for your answers, if something is not explain well tell me to try explain it better . Thank you! How can I get a specific Floor in my Tower? I really really want a specific floor () in my Tiny Tower.  How does the game decide which exact business will go into the "Creative" floor?  Do I have to meet requirements (such as tower height) to unlock certain floors? Uniform convergence of derivatives, Tao 14.2.7. How do I get permissions to edit system configuration files? I can't seem to edit and save config files in the root system (eg: /etc/dhcp/dhcpd.config); it just says "permission denied" or the save option is blocked in the text editor.  I'm pretty sure I'm a root user, but how do I make sure? If I am a root user, how do I fix this? Why should the first person pronoun 'I' always be capitalized? Default constructor with empty brackets How to easily map c++ enums to strings Our admins deployed a new version of Notepad++ (version 6.3) on our machines, and this version is highlighting all changes done in a file by default. It does so by setting the background color of every modified line to a bright orange, which I find very distracting.  We  have dozens of plugins installed, but I double checked and we do not have the "Change Markers" plugin (which could be the culprit).  Any idea where I can disable this feature? Changing the highlight color could also be an option. We've just been learning about complex numbers in class, and I don't really see why they're called numbers.  Originally, a number used to be a means of counting (natural numbers).  Then we extend these numbers to instances of owing other people money for instance (integers).  After that, we consider fractions when we need to split things like 2 pizzas between three people.  We then (skipping the algebraic numbers for the purposes of practicality), we use the real numbers to describe any length; e.g. the length of a diagonal of a unit square.  But this is when our original definition of a number fails to make sense- when we consider complex numbers, which brings me to my main question: what is a rigorous definition of 'number'?  Wikipedia claims that "A number is a mathematical object used to count, label, and measure", but this definition fails to make sense after we extend $\mathbb{R}$.     Does anyone know of any definition of number that can be generalised to complex numbers as well (and even higher order number systems like the quaternions)? How can I change the class of an HTML element in response to an onclick or any other events using JavaScript? Word to describe using sarcasm or a similar approach to lead someone to recognise their own mistake