With shared hosting, your website shares a server with others. All the websites share and split up the server's storage space, memory (RAM), and processing power (CPU). This can cause issues if too many sites need resources at once.
Cloud hosting is different. It uses virtualization technologies to establish a dedicated storage cluster for your website. The storage is redundant - it's copied across multiple locations. So, if one storage location goes down, the others can still serve your site's data. The processing power (CPU cores) and memory (RAM) can also be upgraded easily if you need more resources to handle traffic spikes or growth.