What does the #TBT and JOTW mean shown before a title?

[SparkleFest]

I went to try to find the answer in the various acronyms threads, but don't see it. It's in green for JOTW and purple for the #TBT. So curious. Thought the OTW of the JOTW might mean Of The Week, but the J?

 

[Ally T]

Throw Back Thursday
Jewel Of The Week

 

[SparkleFest]

to you too! Thanks I would have never figured those out!