# Can you describe what is $S^1 \times [0,\infty)$?

Can you describe what is $S^1 \times$ [0,$\infty)$? Where "$\times$" stands for the product topology and the two factors are with the euclidean topology.

EDIT: What about $S^1 \times S^1$?

• It's a half-infinite cylinder. – Parcly Taxel Jan 30 '18 at 16:32
• Think of an infinite tube or an infinitely long hose. Now cut it in half (i.e., anywhere). – Michael Burr Jan 30 '18 at 16:34