Numbered Definitions, Theorems in beamer

Question

How to get numbered Lemmas, Definitions, Theorems and so on in beamer?

Answer 1

You can set the theorems template with the numbered option:

\setbeamertemplate{theorems}[numbered]

or with the ams style option:

\setbeamertemplate{theorems}[ams style] 

If additionally you use the envcountsect class option by loading beamer in the following way:

\documentclass[envcountsect]{beamer}

then theorems, definitions, and so on to be numbered locally to each section (by default they are numbered consecutively throughout the presentation).