In your Mac computer the size of the dock by default is very small. It makes it difficult to recognize the icons. However you can change a couple of preferences to make it more usable. To do this click on Apple. Form the menu select the dock option and select 'Dock Preferences' from the sub menu. This brings up the Dock preferences window. Here you can change the size of the dock using the size slider bar. You can also set the magnification to the desired level. This changes the magnification of the icons when they are highlighted. This make it easy to see the icons in the dock by highlight them. You can eve set the position of the dock on the screen to either the left, right or bottom areas. This video shows how to change the default settings of the dock on your Mac.