VMware web client 6.0 install

Where is the installation?

I downloaded the Vmware Vcenter VIM setup 6.0 DVD and do not see the install on the disk?

I do see the VSphere desktop client install but no 'web client'.

Do I need to upgrade VCenter server to 6.0 and download the web client from it?

is VCenter server 6.0 backward compatible?  Can I manage an ESXi 5.1 host with VCenter server 6?

Or should I upgrade ESXi to 6.0 before the VCenter server?

Thanks