What kind of insect is this?
That is a flour beetle, the two most common and likely types are the confused flour beetle and red flour beetle but to identify look at the antennae. I'd suggest it is the confused flour beetle because the antenna go from thin to fat quite gradually, though the pictures may not be good enough for that to be certain.

Other commonly used names are tribolium (the genus name) or flour weevil. They are also used in labs as a model organism, groups in my last two labs have used them. They are a pest and you should probably get rid of them.


  "Both types of beetles are often found not only in infested grains,
  but in crevices in pantries and cabinet, as well. Damage to food is
  caused somewhat by the beetles' feeding, but also by their dead
  bodies, fecal pellets, and foul-smelling secretions. In addition to
  creating a foul odor, the beetles' presence encourages the growth of
  mold." - Wiki.