The use of e-mail to market goods and services. E-mail marketing content can be either general or customized. Frequency of transmission to targets can consist of fixed, frequent intervals or sporadic intervals, occurring only when there is something newsworthy to communicate, or else be based upon agreed permissions and registered interest from the receiver. Sophistication (and cost) can be very low or very high. E-mail can also be used to confirm orders of existing customers made through websites and to cross sell to existing customers. E-mail is a new and convenient development of direct marketing. Along with the marketing power of e-mail however, comes the abuse of e-mail, commonly known as spamming, which is unwanted and unsolicited e-mail. While some users fail to distinguish between permission marketing and e-mail spam, spamming is actually a major threat to legitimate e-mail marketers, as a glut of messages could make the entire e-mail medium less effective. It is the online equivalent of junk mail and is starting to be regarded as a public nuisance, but its global medium makes it much more difficult to regulate than junk mail which is delivered through national postal services and can be regulated by national consumer bodies. It is also known as i-marketing, online marketing, digital marketing or web-marketing. See also database marketing; direct marketing; e-mail spam; interactive marketing.