ARPANETARPANETARPANET was the network that became the basis for the Internet. Based on a concept first published in 1967, ARPANET was developed under the direction of the U.S. Advanced Research Projects Agency (ARPA). In 1969, the idea became a modest reality with the interconnection of four university computers. The initial purpose was to communicate with and share computer resources among mainly scientific users at the connected institutions. ARPANET took advantage of the new idea of sending information in small units called packets that could be routed on different paths and reconstructed at their destination. The development of the TCP/IP protocols in the 1970s made it possible to expand the size of the network, which now had become a network of networks, in an orderly way.

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Hard and Soft BounceHard and Soft Bounce

Hard BounceWe consider your account to be "hard bouncing" if the error message we get back from your email provider says either of the following:your email account doesn’t exist your ISP refuses all email from Soft BounceIf the error message we get back from your email provider doesn't fall under the definition of a hard bounce (see above), then the error is considered a soft bounce. If your account generates an occasional soft bounce error, it will be logged but no other action will be taken by Yahoo!7 Groups. However, if your email account consistently generates soft bounce errors for several days, then your Yahoo!7 Groups account will be considered bouncing and your Yahoo!7 Groups account will be deactivated. In this case, you won’t receive any group email until your account is reactivated.

Computer SpamComputer SpamElectronic junk mail or junk newsgroup postings. Some people define spam even more generally as any unsolicited e-mail. However, if a long-lost brother finds your e-mail address and sends you a message, this could hardly be called spam, even though it's unsolicited. Real spam is generally e-mail advertising for some product sent to a mailing list or newsgroup.

Difference between a Difference between a Internet and IntranetInternet and Intranet

There's one major distinction between an intranet and the Internet: The Internet is an open, public space, while an intranet is designed to be a private space. An intranet may be accessible from the Internet, but as a rule it's protected by a password and accessible only to employees or other authorized users.

POPPOPwhere outgoing messages are temporally buffered (stored) before transmission and where incoming messages are stored. The post office runs the server software capable of routing messages (a message transfer agent) and maintaining the post office database.

PhishingPhishingAnyone who has been using email for any length of time has had to deal with the problem of spam or unsolicited bulk email. While spam may at times a nuisance, its only purpose is to advertise a product or service. Within the past few years a new kind of email fraud has arisen that goes beyond advertising into identity theft called phishing.

Encryption and Encryption and DecryptionDecryption

Encryption is the conversion of data into a form, called a cipher text, that cannot be easily understood by unauthorized people. Decryption is the process of converting encrypted data back into its original form, so it can be understood.

NetiquetteNetiquette

Contraction of Internet etiquette, the etiquette guidelines for posting messages to online services, and particularly Internet newsgroups. Netiquette covers not only rules to maintain civility in discussions (i.e., avoiding flames), but also special guidelines unique to the electronic nature of forum messages. For example, netiquette advises users to use simple formats because complex formatting may not appear correctly for all readers. In most cases, netiquette is enforced by fellow users who will vociferously object if you break a rule of netiquette

RouterRouter

A hardware device designed to take incoming packets, analyzing the packets and then directing them to the appropriate locations, moving the packets to another network, converting the packets to be moved across a different type of network interface, dropping the packets, or performing any other number of other types of actions. A router has a lot more capabilities than other network devices such as a hub or a switch which are only able to perform basic network functions. For example, a hub is often used to transfer data between computers or network devices, but does not analyze or do anything with the data it is transferring. However, a network router may take the data being sent over a network, change how it is packaged and send it to another network or over a different type of network. For example, routers are commonly used in home networks to share a single Internet connection with multiple computers.Below are some additional examples of different types of routers used in a large network.