The Mac allows you to adjust the placement of the scroll arrows that are shown next to the scroll bar. You can go to System Preference, select the Appearance section and choose the setting for Place scroll arrows as either Top and bottom or Together. How this actually looks is shown below.

Scroll arrows at top and bottom

Scroll arrows together

What they don't tell you though is that there is a secret third option which is a combination of the two, you get both arrow at the top and bottom as shown here:

Scroll arrows together at top and bottom

Here's how to get this setting.

1) Open a terminal window. You can do this by going to Applications > Utility > Terminal.

2) In the terminal window type the following and press enter: defaults write "Apple Global Domain" AppleScrollBarVariant DoubleBoth

3) Restart programs. Unlike the change made in System Preferences, this change does not take effect in any program that is currently running. You need to Quit the program completely and restart for this change to take effect.

If you change to having your scroll arrows at together at the top and bottom and you change your mind, you can just go back to the Appearance setting and choose one of the existing options. This will overwrite the change made to this setting in the terminal window.