# What is autism? A plain-language guide for parents > What autism is, what it isn't, what "on the spectrum" means, and what to do next if you're wondering about your child. URL: https://theautismkit.com/guides/what-is-autism By The Autism Kit team · Reviewed by [BCBA NAME], BCBA · Updated 2026-09-27 **Short answer:** Autism is a lifelong difference in how a person's brain develops. It affects how a child communicates and connects with others, and often shows up as strong interests, a need for routine, and different reactions to sounds, textures or lights. It is called a spectrum because every autistic child is different. **Key takeaways** - Autism is a **difference in how the brain develops**, not an illness and not the result of anything a parent did. - It affects **communication and social connection**, and usually comes with **routines, strong interests and sensory differences**. - It's a **spectrum**: two autistic kids can look very different. - If you're wondering about your child, **talk to your pediatrician**. You don't need to be sure to ask. ## What does autism mean? Autism, or autism spectrum disorder (ASD), is a developmental condition. It shapes how a child takes in the world, communicates and connects with other people.[3] Doctors look for differences in two areas: 1. **Social communication.** For example, less back-and-forth conversation or play, using fewer gestures like pointing, or finding it hard to read other people's feelings.[1] 2. **Repetitive behaviors, routines and interests.** For example, lining up toys, repeating words or phrases, getting very upset by small changes, deep interest in one topic, or strong reactions to sounds, textures, tastes or lights.[1] These differences start in early childhood, even if they aren't noticed until later. **Autism is not caused by parenting.** Scientists believe autism has many causes, and genes play a large role. [4] Nothing you did or didn't do made your child autistic. ## What does "on the spectrum" mean? "Spectrum" means autism looks different in every child. One child may talk in long sentences and know everything about trains. Another may use pictures or a device to communicate and need help with daily routines. Most autistic kids have a mix of strengths and challenges. A child might read early but find loud classrooms overwhelming, or remember every song but find it hard to say what they need. When a child is diagnosed, doctors often also describe how much support they need, using **levels 1, 2 and 3**. You can read more in [What are the levels of autism?](https://theautismkit.com/guides/levels-of-autism) ## How common is autism? The CDC estimates that about **1 in 31 children** are identified with autism by age 8. Autism is **more than 3 times as common in boys** as in girls, though girls are often identified later.[2] Many autistic kids also have other conditions, such as ADHD, anxiety or sleep problems.[3] Knowing this helps families and doctors look at the whole child. ## What are the early signs of autism? Signs can show up in the first two years. A child might not respond to their name by 9 months, not point to show you things by 18 months, or play the same way every time and get very upset when something changes.[1] Every child develops at their own pace, and one sign on its own doesn't mean autism. For a full, age-by-age list, see [What are the early signs of autism in toddlers and young children?](https://theautismkit.com/guides/early-signs-of-autism) ## How is autism diagnosed? There is **no blood test or brain scan** for autism. Specialists look at a child's development and behavior, talk with parents, and watch how the child plays and communicates.[5] Pediatricians check for autism at the **18- and 24-month** well-child visits. By age 2, a diagnosis from an experienced professional can be considered reliable, though many children are diagnosed later.[5] Here's what the process looks like: [How is autism diagnosed in children?](https://theautismkit.com/guides/how-is-autism-diagnosed) **Talk to your child's doctor if....** your child loses words or skills they used to have, isn't babbling, pointing or waving by 12 months, or you're simply worried. You don't need to be sure. Asking early helps. ## What helps autistic kids? There's no single approach that fits every child. Common supports include speech and language therapy, occupational therapy, developmental and behavioral therapies, and help at school. Starting early often makes a real difference. At home, **visual supports** help many kids: a picture schedule that shows what's next, or a first-then board that makes a change feel predictable. See [What therapies and supports are available for autistic kids?](https://theautismkit.com/guides/autism-therapies-and-supports) and [How to use a visual schedule for your child's morning](https://theautismkit.com/guides/visual-schedule-morning-routine). Free printable: [Free printable: appointment notes](https://theautismkit.com/printables/appointment-notes.pdf) ## What can I do this week? - [ ] Write down 2 or 3 moments that made you wonder - [ ] Book a visit with your child's pediatrician - [ ] Take the 2-minute quiz for one plan to try at home Not sure where to start? The [2-minute quiz](https://theautismkit.com/start) gives you one simple plan for the hardest part of your child's day, whether or not your child has a diagnosis. ## Common questions ### Is autism a disease? No. Autism is a developmental difference, not an illness. Autistic kids can learn, grow and build skills throughout their lives, especially with the right support. ### Do people grow out of autism? Autism is lifelong. What changes is how a child's needs look over time. Many kids gain skills and need different kinds of support as they grow. ### Should I say "autistic child" or "child with autism"? Both are used. Many autistic adults prefer "autistic child"; many parents say "child with autism." Follow your family's and your child's lead. ### Is autism more common now? More children are being identified than in the past, partly because doctors and parents know more about the signs. The CDC estimates about 1 in 31 children are identified with autism by age 8. ## Sources 1. CDC: Signs and symptoms of autism spectrum disorder. https://www.cdc.gov/autism/signs-symptoms/index.html 2. CDC: Data and statistics on autism spectrum disorder (ADDM Network, 2022 surveillance year, published 2025). https://www.cdc.gov/autism/data-research/index.html 3. American Psychiatric Association: What is autism spectrum disorder? https://www.psychiatry.org/patients-families/autism/what-is-autism-spectrum-disorder 4. National Institute of Mental Health: Autism spectrum disorder. https://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-asd 5. CDC: Diagnosing autism spectrum disorder. https://www.cdc.gov/autism/diagnosis/index.html General guidance, not a diagnosis or treatment plan. Talk with your pediatrician or a developmental specialist about your child's care.