I have an assignment that asks me to explain the "order of complexity" of an algorithm. Can anyone explain what that question means? Does that mean what happens first and so on?
Thanks.

actually,in data structure couse we usually find efficiency of our code. it mean that how much our code is efficient.as your question order of growth directly proportional to time complexity and similarly time complexty directly proportional to program steps in your assignment you are required to find step count for example
for(int i=0; i<n; i++)
{
one statement execute;
}
in this example the growth order is n because the loop execute n
n is basically instance characteristics

Well if you don't want to bother with math notation that will probably confuse you more than you actually are, here is pretty good explanation using programmers perspective:

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