There are infinite sets ...

- all real numbers

- all integers

- all complex numbers

- all irrational numbers.

There are very large, but not infinite, sets

- all integrated circuits manufactured by Intel

- all SKUs sold by Amazon

- the cataloged stars in the known universe.

There are sets closer to home

- the students in your class

- the cookie sheets in your kitchen

- the clocks in your abode. (A subset of these would be the ones you have to reset for daylight time.)

- all real numbers

- all integers

- all complex numbers

- all irrational numbers.

There are very large, but not infinite, sets

- all integrated circuits manufactured by Intel

- all SKUs sold by Amazon

- the cataloged stars in the known universe.

There are sets closer to home

- the students in your class

- the cookie sheets in your kitchen

- the clocks in your abode. (A subset of these would be the ones you have to reset for daylight time.)