Linux(Ubuntu) single/dual boot installation

Pranaam to all bhai ji _/\_

in this post, we will go through linux installation on disk  using live cd/bootable USB.
we will discuss about single as well as dual boot installation because sometime , during dual boot installation time we erase whole hard disk :)
so....... lets start 8-)

i have bootable USB drive of BACKBOX linux(its ubuntu based security testing Distro).
boot with live cd/USB
select "boot in live/try without installation" option from boot menu of OS.

you will be at live desktop after few minutes  :) .... like this one

you can access your other partition from this environment too. or you can execute commands/perform other tasks like creating/reading files on other partition and the changes in those files will remain permanent if you reboot or boot in other OS.
this is live desktop and provide all facility like an OS which is installed on HD. the only difference between this and OS on HD is, changes will not remain persistent , i.e if you reboots live OS again, you wot find the os in same configuration as you did before rebooting.

ok lets move to installation process :)
for installation, we will use install ......linux icon on desktop , either double click it or right click on it and select "execute" and it OS will prompt a installation screen which will ask for basic info like this one
select language for OS
 

confirming requirements like minimum disk space. internet connectivity is not required for instillation process :) .

 

ok here comes the important part of installation , selecting the mode of installation.

here we have to select option carefully, wrong option will wipe out your hard disk data :P .

always select option which let you specify installation partition, like something else in above screenshoot or it may be with caption "custom install". This type of install mode will ask that where OS has to be install.
after selecting this option, lets proceed . we will get screen like this (with partition info list on HD)

yessssssssss thats what we want  \m/ . we have list of partitions. now we can create/delete/modify existing partition for our installation. we can create new partition from add option, deletion of old partition can be done by selecting a partition and then clicking delete button. change option provides facility of changing partition format type(ext3/4, fat32, NTFS) of partition, increasing/decreasing size of partition, changing its type(primary/logical) etc.

partition will be listed with device name like /dev/sda1 /dev/sda2 or something like that.

if you want to install linux with windows(on other partition) , then simply dont do anything with that partition which has windows installed (you can recognize windows partition by checking partition format type NTFS and partition size in partition info list) 

for linux installation we need a partition with format like EXT3/4  LVM and many more , but we will use EXT4  partition format. so if you want to install on new partition then create new partition using add button

select free space and click add button

and fill following info

Type of partition should be primary. size of partition atleast 10 GB (use around 40-50 GB if you are using system for installing and testing other things ). format/file system of partition  go for EXT4 , it has nice features :)

select your mount point for partition (will discuss later about mount point)

we have done with most difficult part :)
our partition is ready and we can proceed with installation :)
now just select the partition which we have formatted with  EXT4 format and click on install button .

and installation has been started. now system will ask for few more information like time zone, keyboard layout and username password for system user

huuuuh :D we have done 8-). let system complete process of installation and have a cup of milk  untill it doesnot come to end .
After  completion , just reboot your system and you will get option for either to boot in linux or in windows(if your other partition contains windows partition)
Thank you
Greetz to :- Guru ji zero and whole Team IndiShell _/\_