Either by making them flexible enough to absorb the folding energy without creasing or making them stiff enough resist the folding energy.
I use index cards to study my vocabulary.
Because they are commonly used to make indexes for topics. ie. You would use "index" cards to make an alphabetical index of all the books you've read, guys you've date, etc.
Tell me now
Index cards have many different uses. One can be to write notes on when making a speech, oral presentation or debating. You can use them to categorise different items and hold them in order to create a database. You can make a 'to-do' list on index cards. They can be used as flash cards to learn words or other information.
It quite possibly involves having some folds in the cards, which increases their strength.
You can have index cards as flaps and put the date on the front and when you flap it over, info is on the back
You can make index cards stronger by using thicker cardstock or laminating them for added durability. You can also reinforce them by adding tape along the edges or corners to prevent bending or tearing. Additionally, storing them in a protective container or box can help maintain their strength over time.
You take two identical cards and glue 3 corners together, then leave the 4th for the folding and ripping ( if you know what I mean)
The two cards that you typically use will be for bibliographical information; and notes.
bibliographical information; notes
To creatively fold in cards for unique and personalized greeting cards, you can try techniques like origami folds, pop-up designs, accordion folds, or layering different shapes and sizes of cards. Experiment with different folding styles and incorporate personal touches like hand-drawn designs, photos, or embellishments to make your greeting cards stand out.
You can make a three dimensional pyramid card by twice folding a piece of sturdy paper in half diagonally. Then stand it up so that the center point is at the top.