This question crops up time and time again in conversation, especially in cycling forums and groups.   The answer is no, you don't need a special or specific bicycle to go Bicycle Touring.  Whilst there can be certain factors to consider (i.e. carrying luggage and gearing), fundamentality, any bicycle can be used for touring.  The simplicity of Bicycle Touring is that you only need yourself, a bicycle and the means to carry any kit you wish to bring.  Sort those bits out and you are on the way to having a great time travelling by bicycle.  It is not a race - so if your bicycle moves you forward in the direction you wish to travel, you can use it!

The message here is, don't stress over your bicycle.  As long as it is mechanically sound and safe, it will likely get you where you want to go.  Whether you have a mountain bike, road, gravel, or whatever - get it out, take it for a ride and make sure you are comfortable.  As you become more experienced and fall in love with touring by bicycle,  you may find yourself exploring new bicycles.  But before you invest your hard-earned money, get out and have a few trips first.  Get some experience and work out what you do and don't like.

What are you waiting for?!  Dust your bike down, or borrow one from a friend, and go have an adventure!

Check out this link for converting an old mountain bike into a touring bicycle.  It really highlights what is possible, and won't break the bank.