LaTeX error: Environment … undefined
\begin{name} starts an environment, and LaTeX only knows the ones defined by the document class, a loaded package, or \newenvironment. Any other name stops the compile with this error.
! LaTeX Error: Environment itemise undefined.
Try it: this example has the error
Press Fix it in the error box, and it compiles to a PDF. What pdfTeX printed for it:
! LaTeX Error: Environment itemise undefined.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.3 \begin{itemise}Ready. Press Compile (or Ctrl/Cmd + Enter).
Common causes
- A spelling variant:
itemise,enumarate,tabel. - An environment from a package you did not load:
alignandgatherneedamsmath;tikzpictureneedstikz;lstlistingneedslistings. - A theorem-like environment (
theorem,lemma) used without\newtheoremfirst.
How to fix it
- Correct the name in both
\begin{…}and\end{…}. TeXpad suggests the closest known environment. - Load the package that defines it. For
align, add\usepackage{amsmath}; TeXpad offers this fix automatically. - For theorems, add
\newtheorem{theorem}{Theorem}in the preamble.