> For the complete documentation index, see [llms.txt](https://overleaf-pro.ayaka.space/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overleaf-pro.ayaka.space/latex/latex-errors/22-misplaced-noalign.md).

# 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 **`tabular`** 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:

```latex
%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

Misplaced \noalign.

\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

```latex
\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 **`\hline`** in a table does not need to be preceded with **`\\`**. The problem is our last **`\hline`** which does need to be preceded with **`\\`**. The correct way to write this table is:

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

![Table.PNG](/files/LWIYbAaG71ToP8qMYtiL)


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