Apply pathfinding algorithms on OSM map data

I would like to apply path finding algorithms onto the OSM map data.

Is there anybody who has experience with this who can point me in the right direction as to what steps/procedures I need to take.

Is there any pre-processing that takes place with the osm data beforehand?

I would like to be able to use algorithms such as A*

Yes, you very much need to pre-process the data. OSM ‘ways’ are typically not broken at every junction.

Have a look at the OSRM and Graphhopper projects, which are full-featured routing engines using OSM data.

… or see the OSM wiki about

Thank you, it’s great to see the Open Source code available to some of these Routing projects. As a beginner who has never attempted this before, it is rather challenging to interpret but I will try to break them down.

I can’t seem to find any tutorial or guide online to building such a program, maybe I’ll be a first if I get my head around it!