Name based hosting - In name based hosting multiple websites/domains share the same IP address. All the web traffic reaches the server through IP address. The web server identifies the traffic of each domain and forwards the request accordingly.
IP based hosting - In IP based hosting, a dedicated IP is allocated to a website and it is not shared with any other website. Normally IP based hosting is considered by websites running SSL.
As per Google's latest update, websites with SSL certificate will get higher priority in search engines.