A sitemap may not be needed for a crawler to index your website, but this is a good practice as you are telling robots what page they should index, or to provide information about the images/video/... (=resources) of your website.
The format is an XML file, you can these to generate one
- https://www.xml-sitemaps.com/ (max. 500 pages)
- https://www.sitemapgenie.com/ (no limit, or it seems so)
- You can find some tools on GitHub
Once you created a sitemap, you have to send it to Google/Bing using their platform, as explained in this article about how to submit your website to a search engine.
Notes about the format
The file is looking like this
<?xml version="1.0" encoding="UTF-8" ?> <urlset xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 https://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd"> <url> <loc>https://memorize.be/</loc> <lastmod>2021-08-27T18:11:59+02:00</lastmod> <priority>1.00</priority> </url> </urlset>
- you are adding as many URLs as you want
- the priority is optional
- the field "lastmod" is optional (last time the file was modified, either "YYYY-MM-DD" or the one above)