Gourds are grown for their hard outer shell or fiber rather than for food. Some are grown for the internal fiber and sold as loofah sponges, others are grown for their storage capabilities. Nowadays most gourds are used for ornamental purposes.
Summer and Winter Squash
Summer squash have thin skins and a shorter shelf life. Winter Squash have tough outer skins and have a long shelf life, suitable for getting through most of the winter months.
How can you tell the difference? Ask the farmer!