ICANN publishes the complete list of TLD registries and domain name registrars. Registrant information associated with domain names is maintained in an online database accessible with the WHOIS protocol. For most of the 250 country code top-level domains (ccTLDs), the domain registries maintain the WHOIS (Registrant, name servers, expiration dates, etc.) information.
A domain name, is like the address of your home; web hosting on the other hand, is the space of your house where you place your furniture. Instead of street name and area code, set of words or/and numbers are used for the website’s naming’. The same goes with hosting, computer hard disk and computer memory are used instead of instead of wood and steel for storing and processing data files.
Because web hosting services host websites belonging to their customers, online security is an important concern. When a customer agrees to use a web hosting service, they are relinquishing control of the security of their site to the company that is hosting the site. The level of security that a web hosting service offers is extremely important to a prospective customer and can be a major consideration when considering which provider a customer may choose.
Many services offer so-called unlimited or unmetered service for whatever amount of bandwidth, disk storage and sites you use. It's important to understand that most terms of service actually do limit the definition of "unlimited" to what's considered reasonable use. The bottom line is simple: if you're building a pretty basic website, unlimited means you don't need to worry. But if you're trying to do something excessive (or illegal, immoral or fattening), the fine print in the terms of service will trigger, and you'll either be asked to spend more or go elsewhere.