Documentazione di Ubuntu → Ubuntu 10.04 → Switching From Windows → Installing Ubuntu → Partitioning your disks

## Partitioning your disks

### Single boot - Ubuntu only

If you do not intend to keep your copy of Windows installed on the computer, and you have made a backup of all of your important files, choose the Erase entire disk option from the Prepare disk space screen and then press Forward. The installer will automatically partition your hard disk in a suitable manner.

You are probably used to how Windows represents disks. Your first hard drive partition is usually the C: drive, although this can be changed. Linux has a fixed way of referring to disks, which cannot be changed.

Devices are named differently too:

- The first Master IDE hard disk is called hda.

- SCSI, SATA and USB are referred to as sd.

- Each primary partition is numbered 1 to 4.

- Each logical partition is numbered from 5 upwards.

Hence the first logical partition on the master IDE drive will be hda5.

Partitioning does not occur until you finalize the installation, so you can decide to abort the installation at the very last minute if you require. After finalizing the installation, however, the hard disk will be re-partitioned and all existing data stored on it will be lost. Ensure that you have made and tested a backup copy of all important data.

For more complicated partitioning requirements, select Manually edit partition table from the Prepare disk space screen, and then press Forward. This will start a partitioning tool which you can use to partition your disk yourself. If you are unfamiliar with partitioning, please seek support through an Ubuntu support channel for advice on partitioning your hard disk safely and correctly.

### Dual booting Windows and Ubuntu

You must choose the Manually edit partition table option.

There are a couple of extra steps involved partitioning for dual boot.

1. Resizing existing the Windows partition.

2. Creating the swap partition.

3. Creating the root partition.

4. Creating a separate home partition.

After you have selected the Manually edit partition table option, you will see the Partition Editor screen.

Partitioning does not occur until you finalize the installation, so you can decide to abort the installation at the very last minute if you require. After finalizing the installation, however, the hard disk will be re-partitioned and all existing data stored on it will be lost. Ensure that you have made and tested a backup copy of all important data.

#### Resizing

At the moment your hard drive space is all allocated to Windows. This space needs to be reduced to create space for Ubuntu.

You don't need a huge amount of space for Ubuntu. You will need enough space for the following:

1. Root partition - where Ubuntu is installed. This should be at least 4GB.

2. Home partition - where your files are kept.

3. Swap partition - this need only be twice the size of your memory.

A hard disk can only have 4 primary partitions. However you can create a logical partition instead. This allows another 2 extended partitions to be created within it.

Right click on the Windows partition, which will be formatted as either NTFS or FAT32. Select resize. You can now type in the new size or move the slider.

#### Swap space

Create a partition to use as swap space. Swap space is used by the kernel as extra memory. You will need to make it doubled the size of your installed memory.

Click on the free space and select Create new partition. Select Logical, Swap and set the size to double your system memory.

#### Creating the root partition

The root partition is akin to the "C" drive in Windows. You will need at least 4GB, double if possible. This will allow you more space to install programs.

Select the remaining space (unless you want a home partition). Click Create new partition. Select Logical, Ext3 and set it to use the remaining space. Lastly enter the mount point as /.

#### Creating the home partition

This step is not necessary but will allow you to keep your settings and files in the event you reinstall Ubuntu. Set it up as you would the root partition but choose /home as the mount point.

### Finalizing

Now that it is all configured, review your settings. Make sure you have a root and swap partition and that your Windows partition has a mount point so you can access it.

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