Can someone tell me what is the difference between Bootstrap, Twitter Bootstrap and Bootstrap 3?
In the context of CSS frameworks Bootstrap and Twitter, Bootstrap is one and the same.
Bootstrap 3 is the third major version of Twitter Bootstrap. (When this question was asked, it has not yet been released.)
(There is another unrelated definition: for the initial loading of a computer program or system, you can refer to the launch of certain stages of an early launch. Often this is abbreviated as “loading” as in “loading a computer.” Wikipedia has an extensive definition and etymology , which I will not play here.)
There is no difference. Twitter Bootstrap was the official name of version 1.0 (Twitter Bootstrap). The name was shortened later.
As a Bootstrap came 2 famous guys on Twitter, so sometimes it was called Twitter Bootstrap. Bootstrap 3 is the latest version. (I think version 4 is on its way).
Wikipedia excerpt:
Bootstrap, originally called Twitter Blueprint, was developed by Mark Otto and Jacob Thornton on Twitter as the basis for promoting consistency in internal tools. Before Bootstrap, various libraries were used to develop the interface, which led to inconsistencies and a high maintenance load.
The Bootstrap tag you tagged has a description. Bootstrap is a series of procedures that run when an application starts or receives a request over the Internet.