F ILE O RGANIZATION AND P ROTECTION Topic 5

C ONTENT Files Hard Drives Viruses Optimize Computer System

F ILES A file in a computer system is a sequence of bits stored as a single unit Files are stored on a optical disk, magnetic disk, or electronic storage (Flash drive)

F ILES My system Hard drive is partitioned into 6 sections Three sections are in Linux; not seen by Windows Two sections are C: and D: One section is boot drive (very small) Windows remember things by putting small files here when computer boots DVD-Read/Write Drive Removable Drive, Flash Drive Windows 7 – color codes Red means drive has less than 10% of free space

F ILES

Flash drive, hard drive, DVD – CD ROM drives Tree-like file structure Similar to a filing cabinet Navigate through the levels of your file structure Make folders to store files logically Windows normally installed on C drive Linux operating system Bootable from DVD or CD Bootable from a flash drive

F ILES

Note – my drive is complicated Windows folder – Windows operating system Program folder – Where software programs are stored Note – I have two because I have a 64-bit processor and 64-bit Windows 7 Program folder (x86) means 32-bit programs Program folder means 64-bit programs User folder - stores user data like desktop, My documents, etc.

H ARD D RIVES Important drive for storage and retrieval of large amount of data Data is stored sequentially on magnetic disks Disk is called a platter A read/write head passes over the disk on an arm Hard drives have different speeds 5,400 rotations per minute (RPMs) 7,200 RPMs Faster speed allows data to be stored or retrieved faster Note – new hard drives are solid state Similar to a flash drive No mechanical moving parts More expensive with smaller capacities

H ARD D RIVES

Files should be stored sequentially on drive Fragmentation - Usually Windows put file pieces in different spots File segments are not in sequence Takes longer to retrieve files, especially if drive is over 10% fragmented Hard drive works harder Slows system down, especially for laptops CPU waits longer for stored or retrieved data

H ARD D RIVES Windows has a disk defragmenter Usually slow; completely reorganizes drive No pretty pictures I used Auslogics Disk Defrag Free disk defrag utility Gives picture of drive Organizes files very quickly

H ARD D RIVES

Hard drives can fail Usually after three or more years Hard drive is dropped to the floor Hard drive makes squeaky noises before it fails Data should be backed up External hard drives are cheap Online storage Store files at a website; retrievable from anywhere in the world as long as you have an internet connection Examples Flipdrive Supersync Elephant drive

H ARD D RIVES Windows and Linux When you delete files, the operating system leaves the data there It only changes the file allocation table A table keeps track where the pieces of a file are located A deletion tells the computer that new places are free for new data and files These files are easily recovered Other time, large files like music and movies will be destroyed as new files are written over them Small files like documents, s, and pictures can survive for awhile If you edited a Word document 20 times, those 20 copies may still be on the drive

H ARD D RIVES If you have sensitive data on your drive, never throw your computer or hard drive away. Remove the drive and keep it Physically destroy the hard drive Use a special program to format the drive Changes all information to ones or zeros Quick format does not change the information It only changes the file allocation table Special programs exist that recover data Recuva – a free and excellent program

H ARD D RIVES File compression Some files are large Use compression to reduce file size Not so important for hard drives Hard drives have large capacities and are cheap Important for Limited in attachments for s Common programs Built in Windows XP, Vista, and 7 Winzip 7-zip

H ARD D RIVES Windows (and Linux) fill the drive with junk Temporary programs Installation files Internet files and history Pictures, websites, and content Restore files Over time, this junk can take up giga bytes of hard drive space away Periodically clean this CCleaner – free cleaner

H ARD D RIVES

Registry Cleaner – a program that cleans a computer’s registry Registry – unique to Windows A hierarchical database for the Windows Operating System Configuration settings Software options Tracks the performance of the operating system Do not manually edit the registry!

H ARD D RIVES If the registry is damaged or corrupted, Windows may not work Either replace registry with a backup Or re-install your Windows Operating System To change or edit registry is type regedit on command line Instructor: Uses a registry cleaner to remove unwanted entries Improves speed for a laptop Some do not recommend this! I used Eusing

H ARD D RIVES

V IRUSES Virus – malicious code Create annoyances, like dancing icons on desktop Destroy system files and information Transmission Infected media like flash drive, etc. attachment Install unknown program from internet Visiting malicious websites VirusInfected Computer

V IRUSES Other problems from malicious code Worms – malicious code that replicates itself through a network or internet Worms take advantage of security flaws in a computer User does not have to do anything Origin of spam s, etc. Rootkit – dangerous type of virus Root is the main system directory in Unix (or Linux) Rootkit means a virus has penetrated the system files and has authority to change any system setting Malware – steal passwords, credit card information, etc. Very difficult to detect and eliminate

V IRUSES Spyware – program tries to collect information Keylogger – program that reads characters typed on a keyboard Passwords, etc. Malware Usually does not try to propagate itself Not like a virus or worm Usually user is tricked to download or installing a program

V IRUSES Adware – advertising programs keep popping up in new windows Once a computer is infected, a virus or worm may open a door for more viruses and worms One virus grows into ten or more very quickly

V IRUSES How do you know your are infected? Computer is slower Very long boot time Files mysterious disappears Webpages keep opening up Advertising to remove viruses, worms, etc. This company may have put it there Programs act strangely or crash frequently Anti-virus program is disabled Worse case – destroys the operating sytem

V IRUSES Virus Protection Antivirus Programs Program scans memory, Windows registry, and file system for viruses Takes up resources, especially for a laptop Scans s for threats Usually do not scan for Spyware or Rootkits Usually more programs for these

V IRUSES Antivirus Programs Bitdefender1 Kaspersky2 Webroot3 Norton4 ESET Nod325 AVG Antivirus6

V IRUSES Antivirus programs are not free Computer files need to be continually scanned Antivirus needs to be continually updated Creators continually create new viruses Ignoring updates can jeopardize system Antivirus is normally a subscription You pay for a license per year Usually one license for one computer Prices range from $30 to $100

V IRUSES Kaspersky Antivirus Some say it is the best It made my system sluggish AVG Antivirus Has a free version Does not hog up system resources Very basic protection

V IRUSES Firewall – a program (or hardware) that monitors data flow between a computer and a network or internet Firewall blocks unauthorized programs Comes with Windows Operating System FirewallFirewall for a Network

V IRUSES Windows Firewall Go to Control Panel Firewall is its own option Antivirus programs may also provide a firewall Usually an upgrade Usually adds to the cost

V IRUSES

Antivirus is only partial protections Rootkit scanners; some are free Sophos Anti-Rootkit GMER RootRepeal Dr Web Cure it

V IRUSES Spyware and Malware (not rootkits) Spybot (free program) Immunization – protects internet explorer and Firefox from bad websites Tea timer – prevents changes to msconfig.exe MSConfig is system configuration Type msconfig in command window Tells which programs to load when system is booted Popular place for viruses

V IRUSES Windows Defender Free spyware program for Windows Requires Genuine Windows Another way for Microsoft to check if operating system has a proper license Type winver in command window for this information

O PTIMIZE O PERATING S YSTEM Review Use a cleaner to remove temporary files Use registry cleaner (potentially dangerous) Use disk defrag to defragment a hard drive Important for laptops Use msconfig to prevent certain programs from loading Periodically run antivirus, rootkit scanners, and spyware scanners Keep Windows and Programs updated Patches security problems Usually takes space and makes programs slower