Differences Between Insects and Spiders: Lesson for Kids

Instructor: Mark Boster
Have you ever looked at a cookie and thought you saw chocolate chips, but they were really raisins? Well, sometimes animals look alike, but they are really different. This includes insects and spiders. Do you know the difference?


''Mom, Mom,'' bellowed Ted, ''Eugenia threw a nasty insect on me!''

''I did not,'' said Eugenia. ''It was a spider.''

Is a spider classified as an insect or not? How can you tell?


All bugs are not the same. There is a group of animals called arthropods. Arthropods are invertebrate animals that have a segmented body, jointed limbs, and an outer body that the animals occasionally shed.

Here are a few key points:

  • All insects are arthropods, but not all arthropods are insects.
  • Also, all arachnids are arthropods, but not all arthropods are arachnids.

If this confuses you, let's try to un-confuse you with the first diagram. See, insects and arachnids are both arthropods, but not all of the arthropods are arachnids or insects.

Arthropods include insects and arachnids.


Insects are the largest group of arthropods there is, and in fact, the largest group of any animal on Earth. There are over one million different types of insects on Earth. But how can you tell if a bug is an insect?

  1. All insects must have three pairs of legs. That means they have a total of six legs.
  2. Insects can live almost anywhere on Earth.
  3. At some time in their life, an insect must have wings. Maybe not when they are young, but they may have wings when they are adults.
  4. All insects have three parts, or segments, to their bodies.

Parts of an Insect

The head for eating, seeing, smelling, hearing, and any other senses they may have. All the heads of insects have two antennas and two compound eyes. That means they have two eyes that each see many of the same images, which makes it easier to see motion.

The thorax helps insects get around. Their legs are attached to the thorax.

The abdomen is what insects use to reproduce.

Some examples of insects are ants, butterflies, flies, grasshoppers, and lightning bugs.


So, then what is a spider? A spider is in a group of arthropods called arachnids. Arachnids are a group of animals with the following traits:

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account