No, there is polynomial growth, for example.

[edit]

Here's an example: If you have a theoretical country that uses an average of 1MW of electricity, and it grows by 5% per year, that's exponential growth. If its usage grows by 50kW per year, then that would be linear growth (one type of polynomial growth). Note that in the first year of this, they both grow by 50kW of usage, but they rapidly diverge:

The difference is that 70 years later, the former will be require about 29MW while the latter will require about 4.5MW

No, and in most cases where it has it, it shouldn't... https://www.youtube.com/watch?v=F-QA2rkpBSY

Your comment was meant to be witty, but is actually just uninformed. Exponential growth is a well-defined mathematical concept [0] and distinct from other formulas of growth. And, to specifically address your comment, the exponent in exponential growth is time, so no you cannot just dismiss it as being "some exponent".

[0] https://en.wikipedia.org/wiki/Exponential_growth#Basic_formu...