In the Finder, you use windows a lot. Lots of different windows containing different information. There are a number of ways to display that information depending on your personal preference. There are 4 main display modes which can be selected by clicking the appropriate icon for view selection at the top of the window. They are as follows:
1. Icon View - each item displayed in the window is represented by a stylish and usually colourful Icon which makes it easy to identify it. You will probably find yourself scrolling quite a bit when using this view though. The shortcut to select this view in any window is CMD + 1 (hold the CMD key and press the number 1 key).
2. List View - items are displayed in a scrolling list from top to bottom. You can double-click a folder to move inside that folder (the contents being displayed in the same window) or you can use the small "flip" arrow beside a folder to quickly display its contents in a "tree" format. The shortcut to select this view in any window is CMD + 2 (hold the CMD key and press the number 2 key).
3. Column View - this is my personal favourite. Items are displayed in a list view, similar to above, but each folder you click on opens a new column to display its contents. You can move forwards and backwards through folders quickly, while still being able to see the contents of the "parent" folder or even the "parent" of that folder. Try it out, it's a neat way of navigating. The shortcut to select this view in any window is CMD + 3 (hold the CMD key and press the number 3 key).
4. Cover Flow - personally I find this more useful for folders containing images and movies. You get a scrolling list of items at the bottom and a reasonably large preview of each item shown above it. The shortcut to select this view in any window is CMD + 4 (hold the CMD key and press the number 4 key).
Different views can be useful for different situations, so try them all out and see what suits you best!