A smartphone is a cellular telephone with an integrated computer and other features not originally associated with telephones, such as an operating system, Web browsing and the ability to run software applications. There is no standard definition that clearly delineates a smartphone -- many devices marketed simply as cell phones offer similar features to those marketed as smartphones.
A tablet is a wireless, portable personal computer with a touch screeninterface. The tablet form factor is typically smaller than a notebook computer but larger than a smartphone. The most common type of tablet is the slate style, like Apple's iPad, Microsoft's Surface or Amazon's Kindle Fire. External keyboards are available for most slate-style tablets and some keyboards also function as docking stations for the devices.