Comparisons of these can be found in various publications such as computer magazines. You should compare processors and determine what kind the computer you are considering has. The processor will affect what type of programs you can run and how efficiently and how fast they will run. It is capable of holding a single character. A diskette that can hold 1.44 megabytes can store 1.4 million characters or about 3000 pages of information.
Graphics require a lot more storage than text.
All modern operating systems use RAM memory. When RAM memory fills up, some of the program and data is moved to the hard drive. This slows down the operation of programs. Most computers come with at least 16 MB of RAM memory. This is a minimal amount for many applications.