Research: What are insects?

While creating my initial group of insects, I came to a realisation that I first need to decide what type of insect I want to make. I narrowed my options to three basic types:

• Fictional: Any human made classification of insects do not matter as long as it resembles an insect (means greater boundaries in terms of narrative and how crazy it could look) 
• Non-fictional: Following the description of what insects are, 3 pairs of legs, etc. (doing more research but it would make the design more believable) 
• Hybrid- combining two or more types of existing insects to create a new type of insect (less work but also less challenge and chance to develop skills) 

After deciding to design a non-fictional insect, I researched the definition of insects to help build a specification for my design.Through online resources, I found that insects have the following characteristics:

• invertebrate 
• in the arthropod phylum (they have a segmented body, exoskeleton and joined appendages) 
• 3 parts to their body (head thorax, abdomen) 
• 3 pairs of jointed legs 
• compound eyes (thousands of units which allows for wider angles, more movement and light) 
• one pair of antennae 
• most have wings 

What interested me the most is the difference between humans and insects. Normally I would never think about the anatomy of other creatures. I think it's fascinating that insects are designed to have tough exoskeletons to protect their insides. Furthermore, I am interested in insects with specific evolutionary adaptations like the lichen-coloured katydid that can blend in with it's surroundings incredibly well. My aim is to design an insect that has a fascinating quality that gives it either a defensive or offensive advantage.