Most homes since the 1950's have concrete foundations with brick veneer or fa├žade. If you see cracking in your brick, it could just require cosmetic masonry work. However, it is important to call a professional like Arta Foundations to inspect your walls to make sure it's not an indication of underlying structural damage such as rusting support beams or a sinking foundation.

Types of cracksPossible Cause & repairs
Horizontal cracks high on your wallIf cracks are at the top of your walls & you have steel support beams it most likely is due to pressure built up from the beams rusting. Moisture from your bricks easily seeps into the beams and causes rust. If you notice this, you should call a professional before additional bricks crack.
Horizontal cracks down by foundation/floorThis often indicates structural damage such as settling of your foundation.
Cracks in brick stepsCracks can occur in your brick steps as normal wear & tear. If your stairs are attached to your foundation however, this can indicate foundation settling and requires a professional to repair before more significant damage is done.
Vertical cracking near wall seams on the outside of your homeMuch like horizontal cracks high on your wall, vertical cracking near wall seams (where your brick meets your support beams) can indicate rust collecting from your beams and pushing against your walls. This requires a professional to prevent significant damage.