Final answer:
Henry Boyd, a slave-entrepreneur, invented a durable, easily assembled bedstead with a unique rail fastening system, greatly contributing to his success in business.
Step-by-step explanation:
Henry Boyd was a slave-entrepreneur, which means he was an individual who, despite being enslaved, was able to establish and run his own business. Boyd's most notable invention was a highly successful bedstead with a unique rail fastening system. This reimagining of bed construction made his product useful and popular because it could be easily assembled and disassembled without damage. Boyd's innovation addressed the common issue of beds weakening over time due to frequent assembly and reassembly, offering a more durable and convenient option to customers.