Autism varies a lot from a person to another, some common and general signs and symptoms are :

- he/she dont respond to his/her name
- starts talking later than other children and/or speaks with an abnormal tone (or rhythm)
- dont keep long or focused eye contact
- Appears as he/she dont hear you sometimes
- Prefer to play alone, in his/her private world
- can't maintain a normal conversation
- Performs repetitive movements
- have specific routines (or rituals)
- seems fascinated by special parts of some objects, like the spinning wheels of a toy car...