In default invoice/estimate templates, your company logo is displayed in the top-right corner. In case you have set for a text to appear below the logo (in “Settings” -> “Company Logo”), it will be displayed as well.
But now you can change the logo alignment on your custom templates (edit template -> “Layout” tab -> “Properties” block).
Choose the alignment and click “Preview” to see how it will look like.
Also, you can uncheck “Show logo and text on invoice/estimate” and the logo (with the text below it) will not be displayed on the template.