TF, is abbreviations of TransFlash and later TransFlash is named as microSD cards.
TrashFlash of T-Flash of simply TF was introduced by SanDisk Corporation in 2004 AD as the world’s smallest memory card, approximately the size of a fingernail. TransFlash was specifically designed for being used in mobile phones.
Are TFlash and microSD same thing ?
Yes, They are same but with little different Technology.The microSD has exactly the same dimensions and specifications as the TransFlash and therefore both memory cards are completely compatible to each other.
What is the key difference between SDCard and TFlash Card ?
MicroSD cards do non-memory jobs like Bluetooth, GPS, and Near Field Communication (NFC) while TFlash Card doesnot do non-memory Jobs.
There is security section switch on SD card while TF card does not have such part.
How TFlash later named into SdCard ?
In 2005 TransFlash was adapted by the SD Card Association. After the adoption, TransFlash changed name to microSD.
Credit: http://dougelniski.com/difference-between-sd-card-and-tf-card/