Answer by taking a quote from the following article:

The Tlingit language (English: , ; Tlingit: Lingit [linkit]) is spoken by the Tlingit people of Southeast Alaska and Western Canada. It is a branch of the Na-Dene language family. Extensive effort is being put into revitalization programs in Southeast Alaska to revive and preserve the Tlingit language and culture. Missionaries of the Russian Orthodox Church were the first to develop a written version of Tlingit, using the Cyrillic script to record and translate it, when the Russian Empire had contact with Alaska and the coast of North America down to Sonoma County, California.

Tlingit has a complex system of pronominals, which vary depending on their relationship to the verb. The subject pronominals are incorporated into the verb in its subject slot. The object pronominals are also technically incorporated into the verb (i.e. the verb "complex"), but most are graphically independent. They are divided into three classes, the verbal object, nominal object, and postpositional object. There are also the independent pronominals which are completely separate from the verb and can be used in dependent clauses or in subject or object position.  The pronominals all have related semantic values, and their organization can hence easily be visualized in a table.  The numbers in the first column represent the usual concept of person, i.e. first, second, or third. Story and Naish identified a fourth person, but this term is inappropriate since they did not describe a clear separation between the so-called fourth person and the other impersonal pronominals.  When analyzing a sentence, the pronominal type is given first, then the form (subject, object, independent) is given following a period. This uniquely represents the pronominal as a two dimensional unit. Thus 1SINGULAR SUBJECT is the first person singular subject pronominal, realized as xhat. The RECIPROCAL does not uniquely identify one of the two reciprocal pronominals, but since they are both phonetically identical as woosh, it is generally unnecessary to uniquely identify them.  There is also a notional zeroth person which can be of subject, object, or independent form. This is not realized in Tlingit, instead it is an empty placeholder for analysis.

What are the pronominals?
The pronominals all have related semantic values, and their organization can hence easily be visualized in a table.