User:Annasandri/2

16.09

Introduction on UNIX

UNIX is a family of operating systems, multitasking & multiuser.
It was born from the evolution of a previous project called Multics. In 1983 Richard Stallman wrote the GNU General Public Licence to permit people to work on it and to modify it.
Philosophy:

• write programs that do one thing and do it well;
• write programs to work together;
• make it easy to write text and run programs;
• support interactive use instead of batch processing

Rasberry Pi

The Rasberry Pi is a single board computer designed to host Unix based operative systems.
It was created in the UK by the Rasberry pi Foundation with the aim of bringing programming into education. It permits several machines and users to interact with the same computer.

30.09

Introduction to GIT

Git is a free and open source distributed version control system designed to handle and keep traces of projects like code, processes, images ecc. ecc.
To use a distributed version control system means that everyone has his/hers working copy of the repository that keeps track of his changes and the different releases made by him/her or by his/her colleagues.
For dummies :)
Github is a web repository based on git.

SSH Keys

SSH means sicure shell. It is used to create a secure connection to the device and increase security in a system.
Cryptographic system that uses pairs of keys:

• a public key;
• a private key (which is associated with a machine in particular);

2.10

BINARY LANGUAGE (01)

Comptometer (b. 1887- Dorr E. Felt)

Key driven mechanical calculator invented in the US at the end of the 19th century. It is extremely fast because each key adds or subtracts its value to the accumulator as soon as it is pressed but it still rely on the operator’s knowledge.

George Boole (b.1815 – d.1864)

Inventor of Boolean Algebra (=branch of algebra in which the values of the variables are the truth values true and false, usually denoted 1 and 0 respectively). Boolean Algebra defines the patterns of digital logic.

Claude Elwood Shannon (b.1916 – d. 2001)

He started to create electronics by using this logic: while he was studing at MIT he designed switching circuits based on Boole's concepts. He came out with the idea of what can be considered as the actual binary code.

Augustus De Morgan(b.1806 – d.1871)

He was a British mathematician and logician who formulated De Morgan’s laws: “the negation of a disjunction is the conjunction of the negations; and
the negation of a conjunction is the disjunction of the negations;”