# Help on lim sup and lim inf

funcalys
Hi everyone,
I'm currently having problems with these concept, my textbook states that:
Let S be the set of all subsequential limits of s_n, then
sup S= limsup s_n
inf S= liminf s_n
Knowing that S is also the set of all limits point of s_n, however I'm wondering how I could determine this set.
Ex: For s_n=$\frac{1}{n}$, I can easily check that 0 is its limit point but I don't know how to find it.