The present chapter is a comparative presentation of the characteristics of milk produced from ruminants – cow, buffalo, goat, sheep, yak, camel - and equids - donkey and horse -. Emphasis is on topics associated with technological and nutritional/biological performance of milk, i.e., fat globule, casein micelle, enzymes, minor compounds. The detailed composition of the complex lipid, protein and mineral fractions of each milk kind is reviewed compiling recent and fundamental publications. The profile of minor components with nutraceutical potential, i.e., nucleotides, polyamines, oligosaccharides, vitamins, is discussed. In some cases, similarities with human milk, technological performance or digestibility are reported. Although the number of reports is not similar for all species, it is evident that within the group of ruminants, goat and camel milk exhibit the important particularities in their lipid, protein and serum fraction. Equids milk is largely differentiated from ruminants counterpart regarding composition, technological behaviour and potent biofunctionality.