The paper describes the characteristics, receptor profile and functions of T lymphocyte subpopulations (helper, cytotoxic, regulatory, memory and others). Among T helper cells one can enumerate Th0, Th1, Th2, Th9, Th17, Th22, T(FH) and nTh2, while T cytotoxic cells include Tc, NKT, Tγδ, and T CD8αα (IEL). Among regulatory cells there are nTreg, iTreg, T(R)1, and iT(R)35, as well as T lymphocytes with CD8, such as CD8+CD122+, CD8+CD28-, and CD11c+CD8+. And among memory T cells there are Tcm and Tem. Moreover, there are some so-called other T cells, such as Tn (T αβ CD4+ and T αβ CD8+), T exhausted and T anergic.