The Yiddish bookmarklet contains a selection of Yiddish online dictionaries, a virtual Hebrew keyboard and a transliteration function for Yiddish web sites.
By clicking the bookmarklets from your bookmarks toolbar, a dictionary menu will appear on your browser screen. Any word you enter in this menu (or any word you have selected from a web site before) can be looked up in one or more online dictionaries which are listed below the input field. You can also look up a specific word on a web site by selecting it with the cursor and then running the bookmarklet bookmarklet afterwards by clicking on it.
YI dicts Yiddish dictionaries, keyboard input and transliteration
It's easiest to understand the concept of the bookmarklet by simply clicking this DEMO.