Why are there different types of outlines/handles?

[a2z (Schriër)]

I’ve noticed this a few times while opening .ttf files, is there a way to remove this, or add it to the other glyph? Sorry if my explanation is bad, I don’t really know what this is.

Weird:

Standard:

[mekkablue (Rainer Erich Scheichelbauer)]

TrueType (quadratic) and PostScript (cubic) curves. Toggle with Path > Other > Convert to Quadratic/Cubic.

[a2z (Schriër)]

I knew it’d be something simple. I just didn’t know what to Google.

Thanks Mekka.