Pregancy tests?

[Sausagessizzling]

Could someone please explain what the difference is? I see people talking about different types on threads but I can't follow it?
Things like checking for darkening lines? Does that mean you're doing to test every day to check a pregnancy is progressing? I've tried to google it and found some cheap tests but the reviews said they're wildly inaccurate?
Please can someone explain, I've gotten myself so confused.

The lines should darken (if you test early and get a positive) up to and around your af due date as hcg gets stronger. Some people test daily, some don't. Also, I found out I was pregnant twice on the cheap Amazon tests, first at 12dpo and second at 9dpo. They were accurate and clear for me.

Is this positive or am I mad!!

@Sausagessizzling people test if they are ovulating with OPK's (ovulation prediction kits) to tell them when to DTD (do the deed). Then they switch to pregnancy tests 10-14DPO (days post ovulation). They look similar to pregnancy tests but test for a different chemical which is noted on the label.