SSD Web Hosting is the basic/simple hosting of a single website. It's meant for those who want a place of presence on the web. Used by individuals, single owner businesses and/or overall commercial websites. Shared Hosting gives you only what you need for your website.
SSD Web Hosting is an entry-level type of web hosting where one physical server hosts multiple websites (and often hosts hundreds of users). Since each user gets (“shares”) a section of that individual server where they can host their website files, this keeps costs low. Here users share system resources on-demand, receiving a percentage of databases, disk space, CPU, RAM as well as email and FTP accounts. Other resources include the single MySQL server, Apache server, and mail server. Considered the most cost-effective option, Shared Server Hosting offers enough resources for any startup, local business, or personal website.
The differences come down to resources and use-case. With Shared Hosting; you're on a set plan with specific limitations, only upgradeable by purchasing a larger package. Dedicated Hosting is usually placed on Dedicated Servers for larger websites with large allocations of resources at their disposal.