# Misplaced \noalign

This error appears when you have used ** \hline** incorrectly.

# Common Causes

**Using \hline outside a table:**

The ** \hline** command can only be used inside a

**environment. You cannot use it for including horizontal lines elsewhere in documents, such as in title pages, or page headers. An example of this mistake is:**

`tabular`

```
%In your preamble
\title{On the General Molecular Theory of Heat}
\author{A. Einstein}
% In the body of your document
\maketitle
\hline
```

This will generate the error shown below

main.tex, line 5

\hline ->\noalign {\ifnum 0=`}\fi \hrule \@height \arrayrulewidth \futurelet... l.10 \hline I expect to see \noalign only after the \cr of an alignment. Proceed, and I'll ignore this case.

When you want to include horizontal lines outside of a tabular environment, you must use ** \hrule**.

**Using \hline incorrectly in a table:**

When using ** \hline** in a table, every instance except the first must be preceded with

**. An example of this error is shown below**

`\\`

```
\begin{tabular}{|l|l|} \hline
First Name: & Albert \\ \hline
Second Name: & Einstein \hline
\end{tabular}
```

The first ** \hline** command here is fine, as the first

**in a table does not need to be preceded with**

`\hline`

**. The problem is our last**

`\\`

**which does need to be preceded with**

`\hline`

**. The correct way to write this table is:**

`\\`

```
\begin{tabular}{|l|l|} \hline
First Name: & Albert \\ \hline
Second Name: & Einstein \\ \hline
\end{tabular}
```

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