The Samsung Galaxy Note tablets (8.0 and 10.1) support the S Pen and include many of the same features that you find on the Samsung GALAXY Note II like Multi-Windows. The Galaxy Note tablets are like bigger versions of a smartphone minus the phone capabilities. The Samsung Galaxy Tab devices are more similar to a traditional tablet and do not include support for the S Pen. According to the speculation, the 16GB Samsung Galaxy Tab 3 8.0 Wi-Fi only, will launch in White (SM-T3110) during June. The following month, the 16GB Samsung Galaxy Tab 3 8.0 3G in White (SM-T3100) will be released.
You might have noticed the new 'SM' prefix for the two tablets. Samsung's own website has confirmed a whole line of new devices with a model number starting with 'SM'. The new the SM-T210、SMT210R、SM-T210X、SM-T211、SM-T215、SM-T310、SM-T310、SM-T310X、SM-T311、SM-T312 and SM-T315. We're only guessing, but perhaps the 'T' represents tablet.
source: Samsung (translated), BlueRingerMen (translated), SamMobile via AndroidAuthority