The demonstratives in English are this, that, these, and those, possibly followed by one(s) in case of pronouns, as explained below.
Other languages, like Spanish and Georgian, make a three-way distinction. Typically there is a distinction between proximal (objects near to the speaker), medial (objects near to the addressee), and distal (objects far from both). So for example, in Spanish:
and, in Georgian:
Portuguese, Japanese, Tamil and Seri also make this distinction (although in Portuguese, especially in Brazil, the three are currently being reduced to two), but German and French, like English, do not. English, however, once had the three-way distinction of this, that, and yonder.
Arabic makes the same two-way distinction as English. For example هذه البنت 'this girl' versus تلك البنت 'that girl'.
There are languages which make a four-way distinction, such as Northern Sami:
Many non-European languages make further distinctions; for example, whether the object referred to is uphill or downhill from the speaker, whether the object is visible or not, and whether the object can be pointed at as a whole or only in part. The Inuit language Inuktitut and the Yupik languages are particularly well known for their many contrasts.
The demonstratives in Seri are compound forms based on the definite articles (themselves derived from verbs) and therefore incorporate the positional information of the articles (standing, sitting, lying, coming, going) in addition to the three-way spatial distinction. This results in a quite elaborated set of demonstratives.
Although, with the exception of Romanian, the neuter gender has been lost in the Romance languages, Spanish and Portuguese still have neuter demonstratives, in Spanish éste (masculine), ésta (feminine), esto (neuter). Neuter demonstratives refer to ideas of indeterminate gender, such as abstractions and groups of heterogeneous objects.
Classical Chinese had three main demonstrative pronouns: proximal 此 (this), distal 彼 (that), and distance-neutral 是 (this or that). The frequent use of 是 as a resumptive demonstrative pronoun that reasserted the subject before a noun predicate caused it to develop into its colloquial use as a copula by the Han period and subsequently its standard use as a copula in modern Chinese. Modern Chinese has only two main demonstratives, proximal 這 and distal 那; its use of the three Classical Chinese demonstratives has become mostly idiomatic, although 此 continues to be used with some frequency in written Mandarin.
A demonstrative determiner modifies a noun:
A demonstrative pronoun stands on its own, replacing rather than modifying a noun:
There are five demonstrative pronouns in English; this, that, these, those and the less common yonder (the latter is usually employed as a demonstrative determiner; even so it is rarely used in common English).
As is obvious from the examples, English employs the same words for both types of demonstratives. Sometimes a difference is made specific by using the pronoun one (this one, those ones).
This is not the case in many other languages.
In Spanish the difference is less marked; except for the series of singular neuter independent pronouns (esto, eso, aquello), the rest of the demonstrative pronouns are identical to the corresponding determiners (except in writing, where a diacritic may be used to mark the pronouns).
In the above, this sentence refers to the sentence being spoken, and that refers to the content of the previous statement. These are abstract entities of discourse, not concrete objects. Each language may have subtly different rules on how to use demonstratives to refer to things previously spoken, currently being spoken, or about to be spoken.