Footer is the last section of every webpage and mostly contains the copyright and designer details. Along with this Footer do contains all the closing tags of containers that were left opened from the Header section including Body section including Sidebar section till Footer section starts.
As Footer is the smallest section, still it can be very powerful if utilized carefully and intelligently. The Footer section not only closes all the opened containers but also forms a respected and security with the placement of Rights Reserved. Footer can be used for loading Scripts which surely reduces the response time of the Page making Page Load faster than ever.
See: How to test page loading and response time
How Loading scripts in Footer section reduces Page Load?
This happens because the scripts are bytes in size but loads maximum with their feature increasing Page Size thus, increasing Page Loading. But, when the scripts are loaded at last in Footer section till then, the dynamic and the required content appears on the screen and even the servers starts responding to the call of the URL and then, Scripts and their features are added later while the page is for use.
How to make Footer section more useful?
The best thing in blogging is your widgets, mostly; Widgets which are used commonly in Sidebar section but apparently many themes or templates do contain it in Header and Footer section which can work extremely well if optimized and utilized in a systematic manner. You can choose a 3 column or 4 column Widget options for Footer section and can bring good results out of it.
See: What are Widgets & How can they be used in WordPress
The Footer widgets can really bring and add reasons for visitors to stay on our blog or site as when they have reached the footer section this means that they have reached the end of that Page and now going to leave that Page. But, with the proper use of widgets you can let them to search more and stay on your site or you can even ask to like on Social Network(s) and or Subscribe to the Blog.
Rest if you are using your blog as a professional or official website then you can even add few line about your services and or profession to give Page a smooth End.
You can catch some of the sites that are providing services in various fields and thus are providing some useful links for the people who have reached at the end of the page so that before leaving they can either subscribe or join or even move to another site owned by the same.
See: How to add widgets section in Footer in WordPress (if you don’t have)
Hint: many internet users including me like to check out the whole page i.e. till the Footer section, so according to me, we can even place an advertisement would be a worth giving Idea (either Adsense or custom banner)