Breadboards are typically used for prototyping electronic circuits. We will be using a Breadboard for each lab. So, understanding how they work is critical.
Here is a great link explaining how breadboards work:
What is a Breadboard and How Do You Use One
This picture above makes it more clear how each row/column is connected. The metal rows you see above have little teeth that allow the pins of our electronics to go down into them to connect them with other holes in the breadboard.
Here's a view of what the metal teeth look like in the breadboard:
This is a longer and historical look at breadboards, but goes into more depth about how they function:
Breadboards for Beginners