How does placement on the periodic table predict the properties of an element?

I am new to the periodic table. I think that by the placement of an element, you know what kind of properties it has. Is this true? What can you learn about the properties of an element from the placement? What are they?How does placement on the periodic table predict the properties of an element?
It is absolutely true!! As one goes from left to right and one goes from bottom to top, you find trends within the periodic table. An example is electronegativity. A molecule like Cesium or Rubidium gives up valence electrons quite readily so it would have a low electronegativity, while fluorine hangs on very tightly to electrons. You also have similarities in the columns; for example the elements in the far right column (He, Ne, etc.) are not very reactive because they have complete outer shells, while the halogens (F, Cl, etc.) all readily react to accept electrons.