Yes, the restrictions differ depending on the type of TLDs, the country the domain is associated with, and the purpose of the domain used.
The following are some of the restrictions and rules:
1. Domain names can be formed with letters and numbers from the ASCII character set (e.g., a to z and 0 to 9). No other special characters and invalid symbols are allowed.
2. Cannot use a domain name that is already registered.
3. You are strongly advised not to register a domain name that might breach an existing company’s trademark.
4. ccTLDs for Philippines (e.g., .ph, .com.ph, .net.ph) registrant must hold Philippines IC/GST number.
* Other restrictions may apply to other different ccTLDs.
Domain registration is a first-to-file system (first come, first served). Therefore, we recommend you to register the domain in mind first, even if there is no immediate plan to build a website, as the domain may eventually be taken.