Questions & Answers about Tämä leikki on hauska.
Tämä means this (near the speaker).
Finnish has three very common words that all often translate as this/that/it:
tämä = this (physically or mentally close to the speaker)
- Tämä leikki on hauska. – This game is fun.
tuo = that (over there) (visible but not so close)
- Tuo leikki on hauska. – That game (over there) is fun.
se = that / it (already known from context, or not important where it is)
- Se leikki on hauska. – That game is fun / The game is fun.
In your sentence, tämä leikki picks out a specific game that is “here” or very present in the situation: this game.