A direct link to a specific function or feature within a Web page. While a
browser bookmark takes you to a specific page, the bookmarklet will take
you to a function, such as a specific search (including the search phrase) on
a Web page, a tagged location on Google maps and others.
Bookmarklets are possible due to browser support of the
protocol "javascript:" that lets you execute bits of
JavaScript code directly.
Roll Your Own Custom Bookmarklets In Firefox, part 2 Javascript bookmarklets have been around since the early days of Javascript. They're possible because Firefox and most other modern browsers (except Konqueror) offer the special protocol "javascript:" to let you execute bits of javascript code directly.
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