Creating a site within a site (site.website.com)

How to create? And would it help business?

[Strapworks]

Hello Everyone,
I am fairly new to web design so please accept my apologies if I ask a stupid question.

This is regarding websites such as site.website.com.

1. Is site.website.com a different site from website.com?

example - I own website.com that sells various products. Can I seperate out the products to pets.website.com, outdoor.website.com, indoor.website.com, etc.?

Reason being - I have so many products that I sell on website.com that I really feel having "featured" sites that promote specific products would help sales, but I still need all my customers to understand they are still buying from website.com.

2. What do you call this?

3. How do you go about doing this?

4. Would it really help my business?

You can tell from my name what my company is, please feel free to check out my site and let me know if you think this idea I have might work.

Thanks

[Dijkgraaf]

1. Yes they can be, although they can also point to the same site.

2. [en.wikipedia.org...]

3. i) You need to create the sites, either on separate IP addresses or have your web server use host-header.
ii) You need to create entries for the sub-domains in your DNS records.

4. That is not something that we have enough information on to decide.