How to Insert Bold Text in LaTeX

You can write bold text in LaTeX by using the \textbf{} command. The text which should be bold goes between the { and } symbol. See the example in Listing 1 in which "and parts of it" will be rendered bold.

This is text \textbf{and parts of it} are bold.
Listing 1 - Bold text in LaTeX.
A LaTeX PDF containing the bold text
Figure 1 - The resulting PDF.

Remember that LaTeX treats spaces and new lines differently than regular word editors like Microsoft Word. A new line doesn't create a new paragraph, it just adds a small space between two lines. So, if you switch lines between bold text, LaTeX will consider them as spaces, not new paragraphs.

\textbf{This is a bold text. This is
still the same bold text.}
Listing 2 - Bold text in LaTeX which contains a new line.

Even though there's a line break between "This is" and "still the same bold text.", LaTeX will treat it as a single space.