I want to create a multiple subdomains, but using only one wordpress and database installation. The difference of those subdomain sites are the colors and the blogs, but in terms of functionalities, layout, plugins, they are just the same.
Is this possible, or can I only go with the ratio 1 is to 1 (1 wordpress for 1 subdomain)?
you can achieve that in many ways, maybe the most suitable for you is to use the multisite function in WordPress 3.0
Read more at WordPress.org :
Create a Newtwork
Migrating Multiple Blogs into WordPress 3.0 Multisite