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A Rollover is a technique using JavaScript that lets you change a page element (usually a graphic image). The term rollover refers to the process of "rolling the mouse cursor over the button" causing the element to react (usually visually, by replacing the source image with another image). The part of the term 'roll' is probably referring to older mice which had a mechanical assembly consisting of a hard rubber ball housed in the base of the mouse (which rolls) contrary to the modern optical mouse, which has no 'rolling' parts. The term ‘mouseover’ is probably more appropriate considering current technology.

Some common uses of the rollover include; inviting user interaction by causing text elements in a menu to "pop up" or otherwise become lively as you roll the mouse over each line, causing a previously invisible graphic image or other element to suddenly appear when the user rolls the mouse over a particular page element, have one element on a page change color as you roll the mouse over other elements.

Animated rollovers are good for making a webpage interactive and can, if used correctly, make it look very professional. There are some disadvantages of using rollovers, such as; mobiles (especially apple products) won't be able to see the rollover if it is flash orientated.

An E-card is like a postcard or greetings card apart from the fact that it is created using digital methods instead of traditional materials like pen and paper. E-cards are made available by publishers on specific Internet sites where they can be sent to a recipient, usually hyperlinked or attached for download within an e-mail. It is also considered more environmentally friendly compared to traditional paper cards as the carbon footprint of the card production is generally much lower compared to paper card production. E-cards are more versatile than traditional greetings cards. For example; E-cards can be easily sent to multiple people at once, can be extensively personalized and digital video E-cards have even begun emerging. Typically, the sender chooses their E-card from an on-line catalogue on a publisher's web site. After selecting a card, the sender can personalize it (eg: by adding a message, photo, or video). Finally, the sender specifies the recipient's e-mail address and the web site delivers an e-mail message to the recipient on behalf of the sender.