What’s an inode?
From linux-mag.com
In the electronic pages of Linux Magazine, file systems are commonly discussed. It’s a fact! In these discussions you might see the term “inode” used in reference to a file system. Fairly often people ask the question, “what is an inode?” so that they can understand the discussion (remember, there is no such thing as a bad question – at least for the most part).
To many people who read these storage articles this might seem like an elementary question but for many people just starting in Linux this concept may not be understood. Plus it’s always good to review the concept but let’s keep any comments civil and constructive (especially if they are directed at the author). Let me also state that I’m not a file system expert so please correct any misstatements but also please give references so people reading the comments can explore the topic.
File systems in general have two parts:
(1) the metadata or the “data” about the data, and
(2) the data itself. The first part, the metadata, may sound funny because it’s data about the data, but this is a very key component to file systems. It consists of information about the data. More precisely it includes information such as the name of the file, the date the file was modified, file owner, file permissions, etc. This type of information is key to a file system otherwise we just have a bunch of bits on the storage media that don’t mean much. Inodes store this metadata information and typically they also store information about where the data is located on the storage media. (more…)