What is autosomal DNA? FTDNA blog

https://blog.familytreedna.com/what-is-autosomal-dna/

What is Mitochondrial DNA? FTDNA blog post

https://blog.familytreedna.com/what-is-mtdna/

What is Y-DNA? Familytree DNA Blog

https://blog.familytreedna.com/what-is-y-dna/