Gourds come in a wide variety of shapes, sizes and colors, but not all of them are edible. The most common type of gourd is the cucurbita pepo, which includes pumpkins, squash and zucchini. Other popular types include the lagenaria siceraria (bottle gourd), cucurbita maxima (hubbard squash) and cucurbita moschata (butternut squash). All of these gourds are edible, but there are also many that are not.
The ornamental gourds that are often used for decoration purposes only include the luffa aegyptiaca (luffa sponge gourd), balsaminoides (balsam pear) and momordica charantia (bitter melon). These gourds should not be eaten as they can cause gastrointestinal distress. Another type of inedible gourd is the wax gourd, which is often used to make candles or other household items. This particular variety is very dense and difficult to digest.
If you're unsure whether a particular gourd is edible or not, it's always best to err on the side of caution and avoid eating it. There are plenty of delicious recipes that use edible gourds, so you won't be missing out on anything by avoiding the inedible ones!