Difference between WordPress Themes and Plugins
Although, themes additionally add a few highlights and usefulness to a site however they are not the same as modules. A module can't change a sites configuration, look and feel yet a subject can do everything. You can redo some usefulness in subjects as opposed to introducing module however themes can't be supplanted by plugin.
A topic is outside impact like a site's introduction and structuring. Though, a module is the inside impact which add or evacuate a few capacities to a site.
Theme sorts out and shows the whole site's data to show it to the visitors.
If you need to change the presence of your site by changing your subject, at that point all the customizations done will be gone (information and data will stay safe). However, you can enact or deactivate a module at whatever point you need. It won't influence the site in any way.
Your site speed is for the most part influenced by planning of subject, number of pictures, reserve control. Number of modules introduced and usefulness code exist as module or topic does not contribute in site's speed.
It's smarter to enable themes to deal with the appearance of a site and module to deal with how a site ought to carry on. In this manner, when topic will be changed, every one of the functionalities of site will remain there.