Embedding your fonts ensures that the PDF takes on your fonts, so that other systems can also display your file correctly, with the fonts used by you, avoiding printing mistakes
A simple of doing so would be to save your file as PDF/X-1a(2001) standard format, using Adobe programmes (available in both Photoshop and Illustrator).This way the fonts are automatically embedded and also ensures that all images are converted to CMYK.
Alternative: You may also convert your text to contours / outlines. By doing so, there are no more fonts, but will instead be vectors, and guarantees that nothing can go wrong regarding fonts.
You first select the text block and subsequently Type > Create Outlines.
Note: Before you begin this process, it is advisable to save your file under another name, since you will not be able to revert outlines to text at the end of the process.
Since it works with images (i.e. pixels) and not vectors like Illustrator, the process to outline fonts is called rasterization. To rasterize text, there are two ways as outlined below.