Flash fiction is, simply, very short fiction. Read a little about it here. I like playing with it. It's like Twitter for short stories.
Here's some examples I had fun with for a contest I lost. This particular contest wanted fiction of 30 words or less. I can report the rejection letters for flash fiction read exactly like rejection letters for any fiction.Only shorter.
He'd been drunker but not lately. He faded awake at the end of a bad
dream. Neither the drink nor the dream explained the dead girl beside
The bus pulled into the station; he was waiting. I could feel his arms
around me; his voice whispering, 'I love you.'
The bus emptied, idling; I turned my head.
THAT was no contrail in the western sky. Al thought maybe the Ruskies
were after Alaska again and called 911, but it seemed no one else had
read the directive.