Let's pretend, neurotypicals, that you're high-functioning autistic. How would your day change? Would you be able to work, eat lunch at a restaurant, go grocery shopping, make phone calls…or even converse with your friends? How many things did you do today that required interaction with other people?
Say you're going grocery shopping. You don't need a list; it's been memorized at home. As soon as you walk into the store, you notice a light is flashing on the ceiling. Someone has a cart with a squeaky wheel. The cheese bar and the cosmetic section have filled the store with a smell: half old socks, half fake roses. You start filling a basket with produce, but the onions are missing. It's alarming; you have a map of the store in your brain and you should know where everything is. An employee walks by and says "Are you looking for something?"
You are, but he popped out so suddenly you don't have any time to figure out what to say. He's halfway across the aisle before you know how to ask where the onions are. "That display, to the right." But you don't know which way right is. You'll have to go first one way, then the other.
At the checkout line, someone is right behind you. You keep twisting around to check for some unknown danger; everyone stares oddly. When the cashier asks what kind of bags you want, you announce "A light is flashing on the ceiling", before remembering it's bad to say random things.
In the parking lot, someone honks and you drop your bags in surprise. The oranges roll out and some innocent passerby stops to help, inadvertently making everything worse. You don't know what to say to him. He has a loud alarming voice. You squawk at him, flap your arms like a chicken and put your sweater over your head, where it stays until you get home, imagining that the strange man will go home for dinner and tell his wife about the mentally disturbed person at the store.
But at home, things are much better. Nobody is going to honk a car horn. You don't have to look behind you. At home is a good place to work. And once you start working, a bright blue elephant could walk by and you wouldn't notice. As an autistic, you can focus on one thing for hours at a time. If the computer crashes and you lose your progress, you can remember what you did and redo it. This is the positive side of being mentally different.