For LPAs there is one to cover property and financial affairs such as dealing with your house and bank accounts and another one to cover health and welfare decisions which includes where you live and what medical treatment you will or will not receive. You can make just one type, but most people tend to make both at the same time.
There are other types of Powers of Attorney as well. Enduring Powers of Attorney (EPA) which can no longer be made and were replaced by LPAS on 1st October 2007 but they can still be used if validly executed; Specific or General Powers of Attorney which tend to be more short-term documents (usually a year) and require the Donor to retain mental capacity at the time of use.