TITLE: discrete math: is there a difference between $\subseteq$ to $\supseteq$
QUESTION [6 upvotes]: I have a question which asks if $X \supseteq I$.
Is it just the same as $I \subseteq X$?
Because I never saw it the other way around or learned about it, I'm confused.

REPLY [7 votes]: Wikipedia article about subset says:

If $A$ and $B$ are sets and every element of $A$ is also an element of $B$, then:

$A$ is a subset of (or is included in) $B$, denoted by $A \subseteq B$,

or equivalently

$B$ is a superset of (or includes) $A$, denoted by $B \supseteq A$.