Learn German: Der Bus hält hier.

Yes, the infinitive is halten. It is a strong verb, which means it changes its stem vowel in the du (you) and er/sie/es (he/she/it) forms. For halten, the a becomes an ä. Since der Bus is a third-person singular subject (acting like 'it'), we use the form with the umlaut: hält.

Wait, shouldn't the verb ending for the third-person singular be -t? Why isn't it hältt?

You are right that the standard ending is -t. But because the stem of halten already ends in a t (halt-), adding another t would be awkward to spell and pronounce. German grammar simplifies this by merging them, so you just write hält instead of hältt.

Doesn't halten usually mean 'to hold'?

Yes, halten is the most common word for 'to hold' (like holding a book or a bag in your hand). However, when talking about vehicles, public transport, or traffic, halten is the standard verb used to mean 'to stop'.

Why does the bus take der instead of das?