Your recipe calls for semisweet chocolate (i.e. the bar kind), but all you have on hand is semisweet chocolate chips; can you use the chips instead?
Possibly, though it depends on your recipe. If you're making brownies, cookies, or other simple batters or doughs, the chocolate chips should work just fine. If you're making molded candies or using the chocolate for dipping or coating, stick with the bar chocolate.
The reason? Chocolate chips are designed to keep their shape when heated, so they don't melt as smoothly or temper as easily. And, chocolate chips tend to be too thick for dipping or coating.