There are primary two different types of foundations that are used today in building basement and crawlspaces foundations concrete poured walls and block walls and occasionally you will see wood foundations and in older homes there will be stone foundations.  


Every basement wall should look at closely, for cracks and movement.  One way we recommend viewing every basement wall is by standing in the corners and looking for movement from each of the corners.  Most cracks found in basement walls the basement are not of any structural concern, but they may be a concern for leaking.  If water stains or signs of water are found we recommend having the crack repaired by a water proof damping company.  If you have found the basement walls are not straight when viewing we recommend having a professional review to make sure you have no major structural concerns.  Weather a basement is finished of unfinished, it has been estimated that 90 to 95 percent of basements will experience some kind of water penetration problem.