I\'ll explain how the Danish military works to the best of my knowledge (which isn\'t the greatest on that subject). I suspect it\'s quite a bit alike in Finland.
When you turn 18 you have to \'do time\' in the military (sorry, can\'t find the right word for it). So you have to go through some tests and stuff so they can see that you\'re fit for it. When it\'s all done and they have made sure you\'re fit for it, it\'s time to draw a number from a large \'box\' of numbers (again, I can\'t explain it better). The thing is, the army only needs a certain number of recruits each year, so if the number you draw is higher than XXXX (depends on the year etc.) then you don\'t have to enter the military - you can however, volunteer if you wish.
If you\'re unlucky (or lucky depending on your mood) you\'ll have to serve the military for 3-18 months depending on your \'position\'. You can (to a point) decide for yourself where you want to be placed (which also determines how long you have to be there). Then when the time\'s up you have finished your time in the military and won\'t have to ever come back (at least when there\'s peace
). Again, you can get a career in the army if you so wish.
You can even refuse to do your time, but then you\'ll have to work in a kindergarten or something for like 6 months.