سلام به همه.لینک گروه تلگرامی که یکی از بچه ها زحمت کشیدن و ایجاد کردن برای درس مباحث ویژه و مباحث رایانش ابری...لطفا خودتون در صورت علاقه و یا دوستاتون رو دعوت کنید....تشکر
https://telegram.me/joinchat/BqeKagBFgLEiPztipc_6KA

Open data is the idea that some data should be freely available to everyone to use and republish as they wish, without restrictions from copyright, patents or other mechanisms of control

ارتباط پایگاه های داده رو در این شکل ببینید....چقدر جالبه!!

The goals of the open data movement are similar to those of other "Open" movements such as open source, open hardware, open content, and open access.

Closed data
Several mechanisms restrict access to or reuse of data. They include:

1/making data available for a charge.
2/compilation in databases or websites to which only registered members or customers can have access.
3/use of a proprietary or closed technology or encryption which creates a barrier for access.
4/copyright forbidding (or obfuscating) re-use of the data.
5/patent forbidding re-use of the data (for example the 3-dimensional coordinates of some experimental protein structures have been patented)
5/restriction of robots to websites, with preference to certain search engines
6/aggregating factual data into "databases" which may be covered by "database rights" or "database directives" (e.g. Directive on the legal protection of databases)
7/time-limited access to resources such as e-journals (which on traditional print were available to the purchaser indefinitely)
webstacles, or the provision of single data points as opposed to tabular queries or bulk downloads of data sets.
8/political, commercial or legal pressure on the activity of organisations providing Open Data (for example the American Chemical Society lobbied the US Congress to limit funding to the National Institutes of Health for its Open PubChem data)

هرم طبقه بندی اطلاعات با یک مثال ساده