Best program for compressing/uncompressing ZIP's on a Jr?

[OldComputerGuy]

So what is it that I would be looking for?

Also, are other compression algorithms like .ARC and .LZH supported?

[Trixter]

zip, arc, and lzh originated on DOS systems, so there are certainly DOS utilities for handling them:

ARC: You can use SEA ARC to make them, but most people use pkunpak to extrac them
LZH: LHA (lharc)
ZIP: PKZIP and PKUNZIP (2.04g has worked best for me; I've had issues with 2.50)

Your friendly neighborhood SIMTEL archive, or archive.org, can turn these up.