In recent years a variety of sub-Doppler cooling techniques, including polarization gradient cooling, gray molasses cooling, and Raman sideband cooling, have enabled the cooling and trapping of single atoms in optical tweezers. Experimental platforms leveraging ultracold neutral atoms in optical tweezers and optical lattices have become an increasingly popular setting for studying quantum computing, quantum simulation, and precision metrology. Atoms with closed cycling transitions, capable of scattering many photons with a low probability of decay into other states, are common choices of species for ultracold neutral atom experiments. The lowest-energy fine structure transitions in alkali atoms enable fluorescence imaging, while a combination of hyperfine and Zeeman sublevels can be used for implementing sub-Doppler cooling. Alkaline earth atoms have also gained popularity owing to narrow-linewidth cooling transitions and ultra-narrow optical clock transitions.