V.T. Dolgopolov Institute of Solid State Physics, Russian Academy of Sciences, Akademika Osip'yana str. 2, Chernogolovka, Moscow Region, 142432, Russian Federation
Experimental and theoretical research into the integer Hall effects is reviewed, together with other transport phenomena in a two-dimensional electron gas in a quantizing magnetic field. Particular emphasis is placed on primary experimental data, on the comparison of experimental and theoretical results, and on the analysis of theoretical predictions from the point of view of their experimental verification. Among experiments of recent years, those that raised questions to be resolved are highlighted. Possible directions for further research are suggested.