I am using ubuntu 19.04. I want to delete fully and install fresh Ubuntu 18.04. And also I don't want to keep any information ,data inside it. When I searched in internet for the Installation type that is partitioning part, I became fully confused. Can you kindly tell me how should I partition hard disk. Swap partition, home partition, ext4 partition in details. Remember I don't want to keep neither 19.04 version neither any data in my laptop. Thanks in advance.
Default Ubuntu installation options are pretty much all you need.
Reinstall, and on the "Installation type" step choose:
"Erase disk and install Ubuntu"
I used this default installation method on my 120GB (111.76GiB) SSD and the following partitions were created:
$ sudo parted -l Model: ATA Samsung SSD 850 (scsi) Disk /dev/sda: 120GB Sector size (logical/physical): 512B/512B Partition Table: gpt Disk Flags: Number Start End Size File system Name Flags 1 1049kB 538MB 537MB fat32 EFI System Partition boot, esp 2 538MB 112GB 111GB ext4
Note: From Ubuntu 18.04 a swap file rather than a swap partition is used.
With 8GB of memory, the default installation created the following swap file:
$ cat /proc/swaps Filename Type Size Used Priority /swapfile file 2097148 308 -2