Why are there gaps between adjoining rails?

Answer 1

The gaps are there to allow for expansion and contraction. In cold weather the rails will contract leaving gaps between the rails. In warm weather the rails will expand and the gaps will disappear. The ride in summer or winter probably would not change, because when the gaps disappear, there could be a difference in elevation, but not enough to cause a problem.

Answer 2

Well the gaps allow it to contract and extract or whatever the word is I forgot.

Answer 3

so they can expand in the summer heat without bending