In this survey, we review the historical development of the Carleson problem about a.e. pointwise convergence in five aspects: a.e. convergence for generalized Schr\"{o}dinger operators along vertical lines; a.e. convergence for Schr\"{o}dinger operators along arbitrary single curves; a.e. convergence for Schr\"{o}dinger operators along a family of restricted curves; the upper bounds of $p$ for the $L^p$-Schr\"{o}dinger maximal estimates; a.e. convergence rate for generalized Schr\"{o}dinger operators along curves. Finally, we list some open problems which need to be addressed.