What is the black cloth covering the Kaaba called?

Kiswah is the name of the black cloth covering the Kaaba.

The kiswah is an embroidered textile placed over the cube-shaped sanctuary in Mecca. Its black fabric is decorated with Quranic verses and Islamic calligraphy, traditionally worked in gold- and silver-colored thread. The covering is replaced regularly, with the annual replacement associated with the hajj season.

The modern kiswah is produced in Saudi Arabia at a specialized complex in Mecca. Making it requires large quantities of silk, metallic thread, and skilled calligraphic and textile work. The cloth is assembled in panels so it can be fitted around the Kaaba.

The kiswah is not itself the object of Muslim prayer. Muslims face the Kaaba during salat, while the textile is a covering for the sacred structure. Its color and design have changed over history, although black is the best-known modern tradition.