A black widow is part of the Theridiidae weaver family (who make cobwebs or tangle webs, also known as comb-footed). They build their webs in 3-dimensional space e.g. - the corner of a room. They do this by creating "anchors" and associated support threads. There is no regular pattern of web weaving as they tend to stay up for long periods of time and when repaired, no same pattern is ever followed.
It also tends to to makes its web in dark, quiet places.
It also tends to to makes its web in dark, quiet places.