There are 2 types of weathering; mechanical and chemical.
Mechanical weathering includes the eroding away of rocks by things like wind or water. The constant heat and cooling of a rock; certain minerals will shrink and grow, depending on the temperature an composition. Other examples include freezing rocks (The ice upon a rock will increase pressure upon it, causing it to slowly crack and fall apart) and exfoliation, which is where a rock breaks off into sheets, or layers.
Some examples of chemical weathering include hydrolysis (the breakdown of a substance when in contact of water), oxidation (reaction where a substance comes into contact with oxygen), carbonation (the combination of water with carbon dioxide; creating carbonic acid), and even animals could cause chemical weathering, like Lichen, who produce a certain acid that can dissolve rocks.
Hope this helps! :)