Posts: A Post can be an article, a review, an interview, etc., to display unique content and can be added to any page in WordPress. Posts DO NOT have access to modules available on Title, Author, & Landing Pages. However, Posts can utilize shortcodes for similar functionality as modules.
Landing Pages: A Landing Page allows you to display content that is more dynamic by using the modules available. This type of page has a broader scope, when compared to a Post. Landing Pages have access to modules such as image carousels, media, video, formstack, meet the author, etc. Landing Pages are dynamic, their location and slug can be edited.