Both are traditional Japanese footwear.
Three holes called ``eyes'' are made in the part where the foot is placed, the thong is passed through, and the thong is placed between the big toe and index finger.
Some geta have protrusions called ``teeth'' on the wooden board on which you rest your feet. The characteristic sound made when walking in geta with protrusions is often described as ``karakoro'' or ``karankoron.'' Although the noise may create an atmosphere when walking in a yukata on a festival or fireworks day, or when walking around a hot spring town, it is often perceived as noise in modern towns (it can damage floors, etc.). There seem to be quite a few places that don't allow geta (including Japanese clogs). As a countermeasure for this, sandals with a sandal structure and geta with rubber teeth are also sold. The purpose of putting rubber on the teeth is not only for sound, but also to prevent the teeth from wearing out too quickly on today's paved roads.
Zori sandals have more formality than geta and are considered formal footwear.
In modern times, mass-produced light zori sandals and light sandals (often called ``Setta'') made of vinyl material have become popular, and they are often worn as summer footwear in combination with casual Western clothing.
Recently, it has become popular to have children wear geta and zori sandals, as it is believed that footwear with thongs is effective for training the feet.
As you hold your thong in place and step on the platform, your foot muscles will be strengthened, and it is said to be good for forming the arch of your foot and preventing bunions.
Many people find that the thongs of new geta and zori sandals are painful.
If you purchased the shoes online, it is best to break them in before you use them.
Just wearing them for a few hours a day will help them adapt to your feet and make a big difference.