man: ManualThis command can be used to query the usage of other commands.The PWD:PrintWorking directory displays current directory su:SwitchUser Switch to the root user CD:ChangeDirectory Switch directory ls:ListFiles Lists the files in the directory ps:Process StatusProcess status mkdir:MakeDirectory Create directory rmdir:RemoveDirectory Move directory MKFS:MakeFile system Create file system FSCKFileSystem check File system check cat:ConcatenateUname series:UnixName System name df:DiskFree Free hard drive DU:DiskUsage Disk usage Lsmod:ListModules list module MV:MoveFile Move file rm:RemoveFile Deletes a file cp:CopyFile Replication file ln:LinkFiles Link file fg:ForegroundProspects for bg:BackgroundBackground chown:ChangeOwner changes owner CHGRP:ChangeGroup Changes the user group chmod:ChangeMode Changing the mode umount:UnmountUninstall DD: Should have been based on the function description"ConvertAn copy is named cc, but cc already stands forC Complier", so named "dd" tar:TapeArchive Decompress file LDD:List dynamicDependencies List dynamic dependencies insmodInstallRmmod:RemoveDelete module lsmod:ListModule listUnix: 							The predecessor of the Linux operating system 
Linux: an open source, multi-user operating systemLinusTorvalds: Author of Linux systemsKenelKernel:GNU: GNU is Not Unix  			GNU is not Unix 
OSS: openSource Software Open source softwareLicense: licenseRed-Penny: Red HatTextMode: indicates the character modeGraphicMode: graphical interfaceRoot: Default Linux system administrator accountCommandCommand:OptionCD: change directory To change a directory mkdir: make directory to create a directory rmdir: remove directory to delete a directory rm: remove to delete a file cp: Copy Copy mv: move Moves or renamesISO:Cd-rom image file mount: mount umount: undo mount Unmount useradd: add a user Add a user userdel: delete a user Delete a user groupadd: Groupdel: delete a group Delete a group RWX: read write execute Read, write, execute chmod: Change the permission mode of the files or the directories Change the permission of a file or directory chown: Changes the host properties of a file or directoryApplicationApplication:Rpm: Redhat Packages Manager Package managerVersionVersion:BuildDate: creation dateSummary: Summary descriptionDescription: Description Level: level runlevel: running level chkConfig: check config Checks the system service startup status log: logs quota: indicates the quotaNFS: network file system Export: output service: Service opensource opensource localhost localhost directory total forward forward search query media media autorun automatic running track tracking authentication Successfully deny Deny access aplication Block module Protect Protects the deviceDouble-Click on the mouseinitA. initialize B. initialize C. initialize D. initialize Details Tag Tag Normal accessories Login export export specific special echo output Manager manager environment environment source Source License license signature interpreter feature modification summary summary prepared faile failure dependent Minimal variable development bracket includes action, action standard, process, script, etc. Script execute complete, execute status status message Console control except Except.outsideprivatePrivate restricte quota inordinate excessive compress drop Drop loopback Collision collision transmit 1. Generate, generate, generate, generate, unreachable Confirm confirm session session terminal Operational Running flag Offset Offset invalid invalid Acknowledge Acknowledge Split Platform Platform bandwidthCopy the code