The Atacama Large Millimeter/sub-millimeter Array (ALMA) in Chile is an interferometric array that consists of 66 antennas. Regular observations of the Sun with ALMA, which started in 2016, provide a new diagnostic tool for studying the solar chromosphere. The requirements for solar observations are different from many other observations with ALMA in the sense that the mapped atmospheric layers of the Sun evolve on very short timescales and the primary beam being filled with complex emission. High-cadence (snapshot) imaging is needed for such a dynamic target but it is very challenging. While the development of the solar observing mode is ongoing, ALMA now provides first scientific data featuring, among other things, the imprint of magnetic fields and propagating shock waves.
I will give a brief introduction to ALMA and its diagnostic potential for the Sun. The challenges with carrying out solar observations and post-processing the data will be addressed and first examples for Band 3 and Band 6 data and first scientific results will be presented.