This is an internet slang language. 17 nov 2013 hashtag throwback usually used when someone wants to post an old photo on instagram and expects reactions such as 'awe so cute'or 'that tb means 'text back' so now you know tb means 'text back' don't thank us.
Also know, what does the word TB stands for?
Tuberculosis: A highly contagious infection caused by the bacterium called Mycobacterium tuberculosis. Abbreviated TB. Tubercles (tiny lumps) are a characteristic finding in TB. Tuberculosis is more common in people with immune system problems, such as AIDS, than in the general population.
What is the meaning of #tb?
A terabyte (TB) is a measure of computer storage capacity that is 2 to the 40th power, or approximately a trillion bytes. A terabyte is more precisely defined as 1,024 gigabytes (GB). The prefix tera is derived from the Greek word for monster.