TFW
That feeling when
Example
tfw you realize your FB post isn't going to get a lot of likes

Related Slang
feels | Feelings |
RDF | Real deal feeling |
VE | Very emotional |
KWIM | Know what I mean |
TTTT | To tell the truth |
Meme | A piece of media that spreads via the Internet |
AF | As f*** |
TFW is an acronym that means "that feeling when". It typically precedes a comment about a feeling or an experience lots of people have.
The acronym is usually seen in lower case on Twitter or Facebook. It has also become a popular way to start a meme.