how e-mail works

Email is based around the use of electronic mailboxes. When an email is sent, the message is routed from server to server, all the way to the recipient's email server. More precisely, the message is sent to the mail server tasked with transporting emails (called the MTA, for Mail Transport Agent) to the recipient's MTA. On the Internet, MTAs communicate with one another using the protocolSMTP, and so are logically called SMTP servers (or sometimes outgoing mail servers).

The recipient's MTA then delivers the email to the incoming mail server (called the MDA, for Mail Delivery Agent), which stores the email as it waits for the user to accept it. There are two main protocols used for retrieving email on an MDA:

• POP3 (Post Office Protocol), the older of the two, which is used for retrieving email and, in certain cases, leaving a copy of it on the server.
• IMAP (Internet Message Access Protocol), which is used for coordinating the status of emails (read, deleted, moved) across multiple email clients. With IMAP, a copy of every message is saved on the server, so that this synchronization task can be completed.

For this reason, incoming mail servers are called POP servers or IMAP servers, depending on which protocol is used.

To use a real-world analogy, MTAs act as the post office (the sorting area and mail carrier, which handle message transportation), while MDAs act as mailboxes, which store messages (as much as their volume will allow) until the recipients check the box. This means that it is not necessary for recipients to be connected in order for them to be sent email.

To keep everyone from checking other users' emails, MDA is protected by a user name called a login and by a password.

Retrieving mail is done using a software program called an MUA (Mail User Agent).

When the MUA is a program installed on the user's system, it is called an email client (such as Mozilla Thunderbird, Microsoft Outlook, Eudora Mail, Incredimail or Lotus Notes).

When it is a web interface used for interacting with the incoming mail server, it is called webmail.

Open relay

By default, and for historical reasons, it is not necessary to authenticate oneself to send email, which means that it is very easy to falsify one's own address when sending mail.

For this reason, nearly all Internet service providers lock down their SMTP servers to that only their subscribers can use them, or more precisely only machines whose IP address belongs to the ISP's domain. This explains why travelling users must modify the outgoing server settings in their email clients each time they move to a new home or business.

When an organization's email server is improperly configured and allows third-party users on any network to send emails, this is called an open relay.

Open relays are generally used by spammers, as using them hides the true origins of their messages. As a result, many ISPs keep an up-to-date blacklist of open relays, to keep subscribers from receiving messages from such servers. By +Aman Kumar 

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Learn Hacking From Beginning

Most of us are very curious to learn Hacking and want to become a Hacker, but don’t know where to start. If you are in a similar situation, then this article will most likely guide you to reach your goal.

On a regular basis, I get a lot of emails where people ask me “How to Become a Hacker”. In fact, this question is not an easy one to answer, since hacking is not an art that can be mastered overnight. It requires knowledge, skills, creativity, dedication and of course the TIME. Everyone can become a hacker provided they learn it from the basics. So, if you wanna become a hacker, then all you need is a good source of knowledge that will guide you through various concepts of hacking from the basics.

What Skills do I Need to Become a Hacker?

In simple words, there is no magic to become a  Hacker. But, like anything else that is worthwhile, it takes dedication and willingness to learn. It is most important to have a basic knowledge of the topics such as operating system basics and it’s working, computer networks, computer security and of course programming. However, you need not be the expert in each or any of those topics mentioned. As you gain the basic knowledge of various branches of computer, you can choose any one as your favorite and advance in it.

What is the Best Way to Become a Hacker?

As said earlier, the best way to become a hacker is to start from the basics. You will have to master the basics to build a strong foundation. And once this is done, you’ll be in a position to explore new ideas and start thinking like a Hacker.

There exists tons of books on the market that will teach you hacking, but unfortunately, it requires a set of pre-established skills and knowledge to understand the concepts explained in those books. Also, most of them are not suitable for the beginners who doesn’t know anything about hacking.

Anyhow, I have found an excellent Book for the Beginners that will teach you hacking from the basics. This book is the first step to fulfil your dream of becoming a hacker. When I first read this book, I myself was surprised at how simple and easy it was laid out. I decided to introduce this book for all those enthusiasts as it can be the right source for the beginners who are interested tolearn hacking from the basics. The good thing about this book is that, any one can understand the concepts presented here, without the need for any prior knowledge. This book is called:

This book will take you from the core to the top. It will tell you how to hack in simple steps. Everything in this book is presented in a simple and effective manner. It is a great source for the beginner who would like to become a hacker. This will install a Hacker’s Mindset on you.

The following skills are uncovered in this book:

You will learn all the hacker underground tricks and learn to apply them in real world situations.

1. You will be put into a hacker mindset so that you will learn to think like a Hacker.
2. By learning how a hacker thinks and acts, you will be able to protect yourself from future hack attacks.
3. You will acquire knowledge nonexistent to 99.9% of the people in the world!
4. This underground handbook may get you interested in pursuing a career as an Ethical Hacker.
5. This book is of great value for all those who have a dream to become a Hacker. By +Aman Kumar 

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