French demonstrative pronouns are all based on the on the word ce, which also functions as the singular masculine demonstrative adjective.

By itself as pronoun ce can mean "this", "that" or "it" for both masculine and feminine subjects. When it comes before a vowel or "h" it is contracted to simple c'.

For indirect and disjunctive objects ce combines with lui (him) and elle/le (her) to form celui and celle. The plural of these are ceux and celles.

For added specificity ce can also combine with là and ici to form cela (that) and ceci (this). In reality though, cela is rarely used except in formal writing, and ceci is used in conversation as both "this" and "that".

In informal French ça is used in place is of ce. Ça continues to contract to c' before vowels and "h".