How to check disk space?

To check disk space in a Linux environment, you can use the df command. Here are some common usages:

Check overall disk space:
```
df -h
```
The -h option makes the output human-readable, showing sizes in KB, MB, or GB.
Check disk space for a specific directory: For example, to check the disk space for your home directory:
```
df -h ~
```
Check disk space for another specific directory: For example, to check the disk space for the /tmp directory:
```
df -h /tmp
```

These commands will provide you with information about the total size, used space, available space, and usage percentage for the specified filesystems.