Human

Human (人間 Ningen) is a term sparsely mentioned in the series, but is nonetheless part of the Zelda Universe. According to dialog in Twilight Princess, the term at least applies to Hylians, but would seem to be a wider envelope term that includes others outside their group as well.

Confirmed Human Tribes
Hylians - A people with long and pointed ears who seem to be usually be fair-skinned, that are mentioned to have a penchant for magic. The predominant and most common people of Hyrule. It appears that Hylians are common in lands beyond Hyrule as well, though its possible at least some of these people may be of different tribes and are just similiar to Hylians. Hylians are the most encountered race in most of the Zelda games.

"Round-eared Humans" - There are a number of humans that are round-eared but are otherwise similar to the Hylians in appearance and culture, and often live with them in the same towns, it is unknown as to whether or not these humans belong to a distinct tribe. These particular humans are the majority in Holodrum and Labrynna, and a province of Hyrule, Ordona, is mostly populated with round-eared humans.

To some extent, it is unclear as to which of the earlier games round-eared humans did appear in and which ones they didn't. The reason for this is due to more simple graphics that made it difficult to distinguish small details on a character that didn't have artwork, such as his or her ears. With the improvement of technology, this lessened by the time of The Wind Waker and Four Swords Adventures. They did appear in Link's Awakening and were heavily featured in the Oracle games.

There is speculation among the fan community that these round-eared humans are more truly "ordinary humans" due to their more anatomically realistic appearance, while Hylians and others are different and/or special types of humans. To add to this, some also have theorized that the Hylians are common in early Hyrule but become less common over the course of certain speculated Zelda timelines as the round-eared take their place.

Unconfirmed Humans
Any of the following races could be speculated to be tribes of humans due to various similarities, most notably physical ones, however considerable differences as well as a lack of conclusive proof that they are or aren't human makes it unclear as to whether or not certain races fall into the category.

Gerudo - A dark-skinned, firey-haired desert dwelling tribe of that are almost always born female, and are often warriors and thieves. When a Gerudo male is born, it is a rare and celebrated event, said to happen only once every 100 years, and the male Gerudo usually becomes their revered leader. Gerudo live in the Gerudo Desert of Hyrule, but in the alternate reality Link enters in Majora's Mask, they live as sea pirates on the coasts of Termina.

Gerudo look human and have been rumored to take Hylian males as boyfriends according to one of the Gossip Stones, but because of their strange nature of almost never being born as males, they are an unusual race, which makes it difficult to determine whether or not they can be classifed as humans. If procreation of Gerudo is done through breeding with other humans, this alone would not necessarily be definite proof that Gerudo are humans themselves, as crossbreeding between distinct races and species can often occur in mythology and the fantasy genre which it is inspired by, to which the Zelda franchise belongs.

Ho Ho Tribe - A tribe of seven that come from Wayaway and seek treasure in The Phantom Hourglass.

Though the Ho Ho Tribe has not explicitly been referred to as "human", due to their physical appearance and a lack of supernatural qualities, they likely are.

Lokomo - A tribe of Hylian-like people who are servants to the Spirits of Good and charged with protecting the land in Spirit Tracks.

The Lokomo look like other Hylians, but because of their special magical connections to Spirits and the land, as well as the nature of their afterlives may qualify them as something closer to supernatural beings.

Sheikah - A mysterious red-eyed people who are similar to Hylians in appearance, and have a special role in acting as servants and guardians to the Goddesses and to the Royal Family of Hyrule. They are associated with the element of shadow, appear to favor tactics of stealth and misdirection, and have magical abilities and tools that deal with illusion and secret information.

Sheikah look human, but have magical qualities and powers and a close connection with the Goddesses, and these supernatural qualities may make them a race that is beyond regular humans.

Confirmed Non-humans
There is at least one race that look human-like but are confirmed to not be human at all.

Wind Tribe - Despite being represented by game sprites that may be interpreted as being human-like, the magical Wind Tribe are distinguished as being a race separate from humans in The Minish Cap.