North Americans differentiate between clear preserves (jelly) in which only the juice is used, and jam which uses the whole fruit. Jellies use (usually) only juice and sugar. (Think of the jelly that surrounds the fruit in a good quality marmalade.) If the fruit doesn't have enough natural pectin to jell, then added pectin (such as Certo) is used. You can also make wine jellies. I've made apple jelly, grape jelly, and red currant jelly, as well as strawberry jam, raspberry jam and marmalade. BTW, our Jim make Seville orange marmalade.
The jelly that you are thinking of is gelatin.
MargW