Central processing unit
A Central Processing Unit (CPU) is the main control mechanism of a computer, containing control logic, registers, and arithmetic logic unit (ALU) as well as a memory interface. Some CPUs implement additional functionality, but often other capabilities are provided through peripheral processors that handle such things as input/output (I/O), floating-point arithmetic, and vector processing. All computers contain at least one CPU, but some contemporary computers contain over 1,000.
The purpose of a CPU is to execute programs. Programs are a series of numeric values, where each value indicates a specific operation. Each value is referred to as an instruction, and has a corresponding mnemonic for programming convenience. These values are known as machine code. All of the instructions that can be executed by a CPU are collectively known as the CPU's instruction set. Different CPU models usually implement completely different instruction sets, so that programs written for one CPU will not execute on a different one. Writing programs in machine code is difficult, so programs called assemblers were written to translate mnemonics into machine code, thus increasing the speed of writing, and the reliability of, programs. Since the 1960s, most programs have been written using a Programming Language, which are even easier to use than an assembler.
A microprocessor is any processor implemented on a single integrated circuit, however most microprocessors are CPUs. The largest producer of microprocessors used in general-purpose computers is Intel.
The basic operation of a CPU is the "Fetch, Decode, Execute" cycle. The instruction fetcher fetches instructions from memory. The control logic decodes and executes the instruction. The ALU is used to perform arithmetic and logical operations such as adding a value in memory to a value in a register and storing the result in another register. On some CPUs, some instructions may require additional fetches from memory (e.g., to get or store operands). A program in memory is executed sequentially, with each instruction stored in a different memory location. The instruction pointer (IP) register keeps tracks of the current program position, and is updated (usually incremented) after each CPU cycle.
Prescient Quotes on Police State Hardware Surveillance
- "The progress of science in furnishing the government with means of espionage is not likely to stop with wiretapping. Ways may some day be developed by which the government, without removing papers from secret drawers, can reproduce them in court, and by which it will be enabled to expose to a jury the most intimate occurrences of the home. Advances in the psychic and related sciences may bring means of exploring unexpressed beliefs, thoughts and emotions. 'That places the liberty of every man in the hands of every petty officer' was said by James Otis of much lesser intrusions than these. 1 To Lord Camden a far slighter intrusion seemed 'subversive of all the comforts of society.' Can it be that the Constitution affords no protection against such invasions of individual security?"
- https://charlescarrollsociety.com/2014/02/12/amrd-t-a-i-l-s-plastic-gloves-for-your-computer-american-redoubt - Tails operating system
- https://charlescarrollsociety.com/2014/01/29/amrd-introducing-the-tor-browser-bundle/ - Tor browser
- https://prism-break.org/en - "Opt out of global data surveillance programs like PRISM, XKeyscore and Tempora."
- https://www.eff.org - "Leading the fight against the NSA's illegal mass surveillance program"
- Online Guide to Privacy Resources
- http://www.nocards.org - Coalition Against Unsolicited Commercial Email
- Fetch-Decode-Execute Cycle
- "Help make mass surveillance of entire populations uneconomical. We all have a right to privacy, which you can exercise today by encrypting your communications and ending your reliance on proprietary services."
- "Organization formed in 1990 to maintain and enhance intellectual freedom, privacy, and other values of civil liberties and democracy in networked communications. Publishes newsletters, Internet Guidebooks and other documents, provides mailing lists and other online forums, and hosts a large electronic document archive. Contact: firstname.lastname@example.org. 454 Shotwell Street, San Francisco, CA 94110-1914. Tel: (415) 436-9333. Fax: (415) 436-9993. Executive Director: Sheryl Steele."
- "EPIC was established in 1994 to focus public attention on emerging privacy issues relating to the National Information Infrastructure, such as the Clipper Chip, the Digital Telephony proposal, medical records privacy and the sale of consumer data. EPIC conducts litigation, sponsors conferences, produces reports, publishes the EPIC Alert and leads campaigns on privacy issues. For more information email: email@example.com, or contact EPIC, 1718 Connecticut Avenue, NW, Suite 200, Washington, DC 20009. Tel: (202) 483-1140. Executive Director: Marc Rotenberg."
- "CAUCE is an all volunteer, entirely web-based organization, created by Netizens to advocate for a legislative solution to the problem of UCE (spam). CAUCE began as a discussion group called SPAM-LAW, formed of members who felt that legislation was necessary to stop spam from choking the life out of the Internet. In 1997 CAUCE proposed an amendment to the Federal statute which outlaws junk "faxes" (47 USC 227) to also prohibit junk e-mail, and since then has remained a pre-eminent voice in the anti-spam community. Email: firstname.lastname@example.org. President: Edward Cherlin."