A vaporizer comprising: - a shell having a battery segment and a cartomizer receiving segment, the cartomizer receiving segment defining a chamber having an insertion end distal from the battery segment and a base end proximate to the battery segment; - a cartomizer insertable into the chamber at the insertion end, the cartomizer including: - a cartomizer body dimensioned to hold a vaporizable substance, - a heating element provided within or proximate to the cartomizer body operable to heat the vaporizable substance, - cartomizer electrical contacts provided on an exterior of the cartomizer, - cartomizer electrical circuitry operable to direct an electrical current between the cartomizer electrical contacts and the heating element, and - a mouthpiece in fluid communication with the cartomizer body, the mouthpiece extending from the insertion end of the chamber when the cartomizer is inserted in the chamber, wherein the heating element is activated by the electrical current and is operable to heat the vaporizable substance to a vaporization temperature; - a battery housed within the battery segment; - battery electrical contacts provided between the base end of the chamber and the battery segment, the battery electrical contacts positioned to contact the cartomizer electrical contacts when the cartomizer is inserted in the chamber; and - battery electrical circuitry housed within the battery segment and operable to direct an electrical current between the battery, the battery electrical contacts, the cartomizer electrical contacts, and the heating element, when the cartomizer is inserted into the chamber, the shell including a window provided at the cartomizer receiving segment so that a portion of the chamber is visible from outside the shell. - a shell having a battery segment and a cartomizer receiving segment, the cartomizer receiving segment defining a chamber having an insertion end distal from the battery segment and a base end proximate to the battery segment; - a cartomizer insertable into the chamber at the insertion end, the cartomizer including: - a cartomizer body dimensioned to hold a vaporizable substance, - a heating element provided within or proximate to the cartomizer body operable to heat the vaporizable substance, - cartomizer electrical contacts provided on an exterior of the cartomizer, - cartomizer electrical circuitry operable to direct an electrical current between the cartomizer electrical contacts and the heating element, and - a mouthpiece in fluid communication with the cartomizer body, the mouthpiece extending from the insertion end of the chamber when the cartomizer is inserted in the chamber, - a battery housed within the battery segment; - battery electrical contacts provided between the base end of the chamber and the battery segment, the battery electrical contacts positioned to contact the cartomizer electrical contacts when the cartomizer is inserted in the chamber; and - battery electrical circuitry housed within the battery segment and operable to direct an electrical current between the battery, the battery electrical contacts, the cartomizer electrical contacts, and the heating element, when the cartomizer is inserted into the chamber,