Tumblr is a microblogging platform that allows users to post text, images, videos, links, quotes and audio to their tumblelog, a short-form blog.
Overview
Tumblr is a microblogging platform that allows users to post text, images, videos, links, quotes and audio to their tumblelog, a short-form blog. Additional functionality includes the ability to view the tumblelogs of others, mark which tumblelogs you wish to follow for updates, the ability to "like" and "reblog" the blog posts of others, and the ability to create multiple blogs or group blogs from one account.
Questions regarding to Tumblr can be split into two areas, custom themes and API.
Custom Themes
Tumblr's Custom Themes allow developers to customize or create their own themes which act as a template to control a tumblelogs's appearance.
More information can be found in the Tumblr Custom Theme documentation.
API
The API allows developers to read and write data to Tumblr. Developers can utilize data from the Tumblr API in a variety of different ways, and is accessible from various clients. The API is also useful to attain data that isn't included in the Custom Themes template tags.
More information can be found in the Tumblr API documentation.