Several subgroups of the computer underground with different attitudes and aims use different terms to demarcate themselves from each other, or try to exclude some specific group with which they do not agree, they give more emphasis to a spectrum of different categories, such as white hat, grey hat, black hat and script kiddie.

A Cracker or Cracking is to “gain unauthorized access to a computer in order to commit another crime such as destroying information contained in that system”. These subgroups may also be defined by the legal status of their activities.

Types of hacker

White hat

A white hat hacker breaks security for non-malicious reasons, for instance testing their own security system.The term “white hat” in Internet slang refers to an ethical hacker. This classification also includes individuals who perform penetration tests and vulnerability assessments within a contractual agreement. Often, this type of ‘white hat’ hacker is called an ethical hacker. The International Council of Electronic Commerce Consultants, also known as the EC-Council has developed certifications, courseware, classes, and online training covering the diverse arena of Ethical Hacking.

Black hat

A Black Hat Hacker is a hacker who “violates computer security for little reason beyond maliciousness or for personal gain”(Moore,2005). Black Hat Hackers are “the epitome of all that the public fears in a computer criminal”. Black Hat Hackers break into secure networks to destroy data or make the network unusable for those who are authorized to use the network. The way Black Hat Hackers choose the networks that they are going to break into is by a process that can be broken down into two parts. This is called the pre-hacking stage.
Part 1 Targeting Targeting is when the hacker determines what network to break into. The target may be of particular interest to the hacker, or the hacker may “Port Scan” a network to determine if it is vulnerable to attacks. A port is defined as “an opening through which the computer receives data via the network”. Open ports will allow a hacker to access the system.
Part 2 Research and Information Gathering It is in this stage that the hacker will visit or contact the target in some way in hopes of finding out vital information that will help them access the system. The main way that hackers get desired results from this stage is from Social Engineering, which will be explained below. Aside from Social Engineering hackers can also use a technique called Dumpster Diving. Dumpster Diving is when a hacker will literally dive into a dumpster in hopes to find documents that users have thrown away, which will help them gain access to a network.

Grey hat

A grey hat hacker is a combination of a Black Hat and a White Hat Hacker. A Grey Hat Hacker may surf the internet and hack into a computer system for the sole purpose of notifying the administrator that their system has been hacked, for example. Then they may offer to repair their system for a small fee.

Elite hacker

A social status among hackers, elite is used to describe the most skilled. Newly discovered exploits will circulate among these hackers. Elite groups such as Masters of Deception conferred a kind of credibility on their members.

Script kiddie

A script kiddie is a non-expert who breaks into computer systems by using pre-packaged automated tools written by others, usually with little understanding of the underlying concept—hence the term script (i.e. a prearranged plan or set of activities) kiddie (i.e. kid, child—an individual lacking knowledge and experience, immature).

Hackers can be categorized in any way

The question we asked while watching the above picture

• Hacker type:  Unskilled hackers
  • Attack style:  Use existing tools “as is” with no changes.
  • Defensive strategy:  Constantly updated negative security model (i.e., signatures) to identify known exploits.
• Hacker type:  Semi-skilled hackers
  • Attack style:  Use existing tools, but with some “mix and match” ability.
  • Defensive strategy:
    1. Anti automation – to identify the use of the tools, regardless of their specific functionality.
    2. Online updating reputation services – to automatically learn from the experience of others in a timely manner.

• Hacker type:  Skilled hackers
  • Attack style:  Use genuine new exploits and tools
  • Defensive strategy:Scanner integration to hot patch application specific vulnerabilities – even the best hacker cannot exploit a nonexisting vulnerability.
    1. Positive security model (i.e., profiling) that allows mitigating previously unknown threats by detecting anomalies.
    2. Advanced correlation engines that incorporates both positive and negative security models.
    3. Research team to envision, explore and analyze emerging exploits and threats.

Disclaimer : This information is just for educational purpose. If someone use in malicious activity then only he is responsible for it.

The evolution of online feedback and commenting has come a long way; from the old school guestbook to forum and feedback form, and from native platform-dependent commenting systems to today’s 3rd party commenting systems that work cross-platform regardless of what programming language or scripts your site is based on.

These 3rd party commenting systems do more than just allowing visitors and readers to drop comments. Most of them support comprehensive comment managing backend, spam control, blacklist/ whitelist management, integration with social media, theme customization and much more.
Today, I’m going to bring to your awareness three of the most commonly used (by bloggers and site owners) 3rd party commenting and discussion systems, respectively Disqus, IntenseDebate and LiveFyre. I’ll also discuss some of their key features, what I like and what I think they may lack of. Lastly, at the end of each, I have also thrown in a couple of useful links for your reference.

1. Disqus

Disqus is a mature comment management system and perhaps the most used amongst bloggers and website owners. Introduced back in 2007, it is currently serving more than 750,000 websites. According to a recent study done by folks at Lijit, 75% of the websites using 3rd party commenting system are powered by Disqus.

Whether you are using Disqus for the first time or migrating from other commenting systems, integrating Disqus with your website can be fairly simple. Right after you’ve signed up with Disqus, do check out the Import / Export section to find out more instructions on how to import your existing comments from various platforms (WordPress, Blogger, Movable Type, or other commenting systems) to Disqus.

Disqus is mobile friendly; its interface swaps according to different media so commenting is not affected even if your readers are on mobile browser. On top of that, Disqus also offers a mobile app for the convenience of site owners to manage comments and their communities on the go. Disqus apps are currently available for iPhone and Android.
Leaving comments or responding to a comment on a Disqus-powered system is a bliss, it is almost real time. Latest comments are reflected instantly without the need to refresh the entire page. For site owners, you can (optionally) be notified via email when a comment has been made on your website, and the best part is – you can respond to it right away from your email. And for commenters, you can even attach additional media (photo, link, video, etc) along with your comments.

Disqus’ core platform is free, but if you need more out of your commenting system, Disqus offers 3 subscription-based paid packages, each with their own respective of premium tools.
Here are more Disqus features worth knowing:

• Compatible with search engines, in another word – SEO friendly.
• Integrates with Akismet.
• Allows commenters to post as guest, or login via OpenID or social networks IDs (Facebook, Twitter, Google and Yahoo).
• Allows user to flag comments.
• Easy comment moderation via admin panels.
• Supports blacklist/ whitelist and word filtering.
• Allows site owner to display Tweets and other reactions.

Useful Disqus related links:

• Disqus official website | Sign up
• Disqus features
• Disqus blog
• Disqus premium
• Disqus demo
• Disqus for users
• Disqus for developers

2. IntenseDebate

The easiest way to sell IntenseDebate is probably stating who are the folks behind it. IntenseDebate is an Automattic product, the same guys who brought you WordPress, PollDaddy, Akismet and other cool web services.
If your blog is running on WordPress and you are looking for a 3rd party commenting system for a chance, you know this may be your best bet as IntenseDebate is created and maintained by the same people who coded your blog platform.
Reputation points is one of the key features I like about IntenseDebate. It allows users to reward well-thought and constructive comments with points and have them appear on top of others less quality comments. I find it a pretty good way to encourage higher quality discussion.
IntenseDebate sends an email to commenters whenever someone response to their comment. Not only this is a good way to keep the discussion going, it also makes readers keep coming back!
Similar to Disqus’ comment flagging, IntenseDebate allows you to report any inappropriate comment and on top of that, IntenseDebate allows you to state the reason for reporting.
Another great function of IntenseDebate is that it allows users to simultaneously tweet when they post a comment. It is yet another great way to draw more attention and traffic to the post.
More IntenseDebate features:

• Supports numerous widgets to show off your comment stats, most recent comments, most popular comments and top commenters.
• Allows users to login via OpenID, Twitter, Facebook or even WordPress.com ID.
• Developers can take advantage of the Plugins API to make commenting and discussion even more interesting. E.g., adding PollDaddy polls, embedding YouTube Videos, etc.

I noticed that IntenseDebate seems to be a little slower in terms of loading speed compared to Disqus and LiveFyre. Anyway, it could be my setup or my Internet connection.

Useful IntenseDebate related links:

• IntenseDebate official website | Sign up
• IntenseDebate features
• IntenseDebate blog
• IntenseDebate WordPress plugin
• IntenseDebate help page
• Contact IntenseDebate

3. Livefyre

Last but not least – Livefyre, the latest addition to the 3rd party commenting and discussion system market. They may be new but that does not make them the weakest. And as the matter of fact, pardon my subjective opinion; LiveFyre is my favorite among the three.
It is simple, very human-engaging, easy to use and consists most features we see in Disqus and IntenseDebate.
Livefyre allows commenter to tag other users in their comment using the ‘@’ symbol, pretty similar to what you can do on Facebook. Tagging LiveFyre, Facebook, Twitter users are supported.
Every time you enter a comment, you can also choose to have them posted simultaneously to Twitter, Facebook or both. Similarly you can also share someone else’s comments on Twitter and Facebook.
Whenever someone chooses to “follow” a conversation, they are automatically listening – meaning they will get notification whenever there is an update. Livefyre shows you in numbers, how many commenters are online and how many are listening to a particular conversation.
Other notable Livefyre features include:

• Supports comment votings and user ratings.
• Mobile-friendly interface.
• Centralized admin panel for comments moderation.
• Supports blacklist/ whitelist and spam control.
• Social media (Facebook, Twitter, LinkedIn) sign in.

Useful LiveFyre related links:

• LiveFyre official website | Sign up
• LiveFyre demo
• LiveFyre features
• LiveFyre blog
• LiveFyre help page

If you have experience using any of the mentioned commenting systems, or you’d prefer sticking with WordPress (and others) native commenting systems, I’d love to hear your comment. :)