A Prime Number is: 

an entire number that can’t be made by increasing other entire numbers 

(in case it can be realized by duplicating the other integers,then we are talking about a Composite Number) 

Furthermore, 1 isn’t prime and furthermore not composite. 

Here we see it in real life: 

Here is a rundown of all the prime numbers up to 1,000:

2357111317192329313741434753596167717379838997101103107109113127131137139149151157163167173179181191193197199211223227229233239241251257263269271277281283293307311313317331337347349353359367373379383389397401409419421431433439443449457461463467479487491499503509521523541547557563569571577587593599601607613617619631641643647653659661673677683691701709719727733739743751757761769773787797809811821823827829839853857859863877881883887907911919929937941947953967971977983991997 more…

Examples:

Is 8 a Prime Number? No, just because it can be made by 2×4=8

Is 73 a Prime Number? Yes, as no other whole numbers multiply together to make it.