What is the meaning of |x+3| (absolute value)and what is its purpose? In other words, where would we use this in real life and why?

i know it's important in engineering

but let me show some examples

if you want to make a design for (v) shape
you can use f(x) = |x| (you'll get a good shape with acute angle at (0,0)]

for machines
if you don't want to get any negative values you can program it to |f(x)|

in other words this sign ( | | ) protect us from getting a negative value for every thing

and let's say that you want a program to calculate the distance from the value of x=0 to the value of x = 1
you'll get a positive answer

but if you want the distance from x=0 to x = -1

you'll get a negative answer ! and you know a distance can't be a negative value so we use the (||) and you can say ( |answer| )

you'll know much about it when you become an engineer or study math at a high level