Distributed Transaction VS Local Transactions?

I was reading an article about the way that ADO.NET 2.0 supports
Transactions ,which I was surrounded with some confusing terms I can't
distinguish from :

Terms are as follows :
* Distributed Transactions VS Local Transactions
* Explicit Transactions VS Implicit Transactions
* Automatic Transactions VS Manual Transactions

What I think about this is as follow ,Correct me if I'm wrong,please:

Explicit Transactions are those which you have to explicitly begin and
commit (or rollback) -so they could be considered as **Manual**
Transactions.
Implicit Transactions are those which are done **automatically**.

Distributed Transactions span two or more SQL Servers (2 or more Databases
within a single SQL Server ) while Local Transactions span only one
Database.
now is there any relation between **Distributed Transactions** and **Local
Transactions** and other terms like automatic and explicit and....?

Thanks for your time in advance.

ALi-R