Reproduced Ubuntu Linux Primer (v): Ubuntu usage Basics

Reprinted from http://terrychen.info/ubuntu-linux-beginners-guide-getting-to-know-and-work-with-ubuntu/

In Ubuntu Linux Introduction (iv): Ubuntu Initial setup article, we have completed the basic configuration of Ubuntu, and now we will further learn some of the basic knowledge needed to use Ubuntu Linux.

1. Ubuntu Linux File Management Foundation 1.1 Linux Directory Basics

Unlike the file structure of partition-folder-file in Windows, the file structure in Linux is only "directory--file" level two. /(root directory) is the starting point of the Linux directory tree, and the partitions are mounted to subdirectories below the root directory.

Subdirectories in the root directory have some meaning, and we need to understand the role of some important subdirectories:

• Home directory for all users, storing the user's data and configuration. Users in the system have different home directories under the directory, whose directory name is the corresponding user name.
• /media:windows partitions and removable device mount points.
• /usr: Most of the system programs are installed in this directory.
• /etc: where the system-level configuration resides.
• /tmp: Where the system temporary files are stored.

1.2 Linux Permissions Basics

In Linux, all files have permissions, file permissions are divided into read (R), write (w), and execute (x) three types. For program files, only executable permissions are assigned to execute.

Each file has three sets of permissions to manage, which are owners, groups, and others, which specify the file owner, the group to which the file owner belongs, and the permissions of other users.

File permissions restrict access, modification, and execution of files to ordinary users, and superuser root can access any file on the system.

1.3 Nautilus File Manager

Nautilus is the default file manager in Ubuntu, it is divided into two columns: The left column is the quick navigation bar, you can quickly access the common directory and Ubuntu automatically mount Windows partition and removable device; the right column is used to manage files and directories.

Because Linux does not have c:d: such a drive letter, the Windows partition and the removable device is mounted after the capacity to differentiate. However, because of different calculation methods, the partition capacity is larger than the capacity shown in Windows, consistent with the factory identity of the hard disk.

The documents, music, pictures, videos and downloads in the quick navigation bar are the directories below the user's home directory, and it is recommended that you store your data files in the corresponding directory.

In Linux, files and directories that begin with. are not displayed by default, and the user configuration in the home directory is usually hidden in this way. If you need to display hidden files and directories, you can press the shortcut key CTRL + H in Nautilus.

If you need to modify the file permissions and the program that opens the file, select Properties in the right-click menu, and you can modify them in the Permissions and Open tabs page of the Properties dialog box.

2. Fundamentals of Linux Software Management

In the previous article, we have used Ubuntu Software Center for Software installation. Let's take a closer study of some of the software management aspects of Ubuntu.

2.1 Introduction to Software Installation methods

In Ubuntu Linux, the main ways to install the software are the following four types:

• Software Source installation: For the software in Ubuntu's official repository, we can automatically download and install it from the software source via Ubuntu software package management system, and install the software from Ubuntu Center, which is actually a way to install the software source. This is the main way to install software in Ubuntu.
• Manual Download Installation: For some software not included in the official Ubuntu warehouse, the program author provides a compiled. deb file, we just download the appropriate. deb file, double-click to launch Ubuntu Software Center installation.
• PPA installation: Some software that is not included in the official Ubuntu repository provides the PPA, which is actually an informal software repository. As soon as we add the PPA, we can install the software through Ubuntu Software Center, and see the following article for more details.
• Compile and install: Download the software source code to compile, but usually do not need to install in this way.

2.2 Modifying a software source

Software source refers to a series of servers around the world that store Linux packages, and when we install software and receive updates, it is the package management system that automatically downloads related packages from the software source. Therefore, the speed of the software source directly affects the speed at which the software is installed and the updates are received. Ubuntu default software source in some domestic network environment (such as education Network) is slow, you can switch to faster software sources as needed. The steps are as follows:

1. Run Ubuntu Software Center, click on the Edit menu, select the software source, the system will prompt you to enter the password, enter and click OK.

2. Click the download from drop-down list to select a different site.

3. Click to select the best server, Ubuntu will automatically speed up all the servers in the list, select the fastest server. We can also directly select the domestic faster 163 source mirrors.163.com or Sohu source mirrors.sohu.com, set up after the completion of the click Select Server.

4. Close the Software Source dialog box and go back to Ubuntu Software Center, and the system will start updating the software source information and wait for it to complete.

2.3 Adding PPA

Although the Ubuntu software source already contains a large number of software, but some software is not included in the official warehouse. However, we can use the PPA to add some software that is not included in the official repositories to the software source so that we can install and upgrade the software using Ubuntu's package management system.

With the very powerful Ubuntu Configuration tool Ubuntu Tweak as an example, the steps to add a PPA are as follows:

1. Run Ubuntu Software Center, click on the Edit menu, select the software source, the system will prompt you to enter the password, enter and click OK.

2. Select the Other Software tab and click the Add button.

3. Input ppa:tualatrix/ppa , click Add Source.

4. Close the Software source dialog and go back to Ubuntu Software Center and the system will start updating the software source information and wait for it to complete.
5. You can install Ubuntu tweak by searching for Ubuntu-tweak in the Ubuntu Software Center.

After installing Ubuntu Tweak, we can also add the PPA of the direct-to-use software via the Software Source Center in Ubuntu Tweak, adding a process more convenient.

Now we understand some of the basics that are needed to use Ubuntu Linux on a daily basis. In order to make Ubuntu better, we also need to install some excellent software, please continue to read Ubuntu Linux Primer (vi): Ubuntu Common software recommendations.

Reproduced Ubuntu Linux Primer (v): Ubuntu usage Basics