Battery testing

I asked to have my battery tested at a Pepboys. They said it was ok. But I’m wondering:

Are they simply checking its voltage, or are they testing the integrity of the battery?

Thx

Most parts stores use what is called a conductance battery tester. This type of tester can check the battery’s condition without having to recharge the battery. And it determines the condition of the battery by measuring the cold cranking amps of the battery compared to the CCA’s rating of the battery. Very accurate.

Tester