- Used to store program instructions and data temporarily
- Unique addresses and data can be stored in any location
- Can quickly retrieve information
- Will not remain if power goes off (volatile)
ROM (read-only memory) - Information stored permanently on a chip
- Contains startup instructions and other permanent data
CMOS (complementary metal oxide semiconductor) - Special low-energy kind of RAM Flash memory
- Used for phones, pagers, portable computers, handheld computers, and PDAs
Buses, Ports, and Peripherals - Information travels between components on the motherboard through groups of wires called system buses, or just buses.
Buses - Typically have 32 or 64 wires
- Connect to storage devices in bay
- Connect to expansion slots
- Connect to external buses and ports
- Make it easy to add external devices, called peripherals.
- New laser etching technology called extreme ultraviolet lithography (EUVL) could reduce chip size and increase performance radically.
- Superconductors that transmit electricity without heat could increase computer speed a hundredfold.
- The optical computer transmits information in light waves rather than electrical pulses.
- A computer manipulates patterns of bits—binary digits of information.
- The CPU follows software instructions, reduced to strings of bits, to perform the calculations and logical manipulations that transform input data into output.
- Not all CPUs are compatible with each other.
- RAM (random access memory) as a temporary storage area—a scratch pad—for instructions and data
- ROM (read-only memory), which contains unchangeable information that serves as reference material for the CPU as it executes program instructions
-The CPU and main memory are housed in silicon chips on the motherboard.
Consumer Applications:
-Many software companies have repleaced their printed documentation with
tutorials,
reference matierals
help files
on-line help
Upgrading:
Users can upgrade a program to the new version by paying an upgrade fee to the software manufacturer.
Newer Releases often have additional features and fewer bugs
Compatibility :
it allows software to function proberly with the hardware, operating system, and peripherals
programs written for one typer of computer system may not work no another
Disclaimers:
Software manufacturers limit their liability for software problems by selling software "as is"
Licensing: Commercial Software is copyrighted so it can't be legally duplicaed for distribution to others
Software License
Volume License
Distribution: Software is distributed via:
direct sale
retail stores
mail order catalogs
websites
not all software is copyrighted
Web Applications fall into several categories:
-some simple Web applications perform simple data-processing tasks that could also be performed by traditional programs running on stand alone PCs.
-Most Web Applications take advantage of the Web's connectivity
-Many Web applications leverage the web's as a huge respository of information
-some web applications support online business transactions
-news-oriented web applicationsprovide up to the minute reports on a myriad of subjects
-other web applications support a more traditional form of information broadcasting
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