1.1 Number Systems
Binary is the foundation of computer science and is an excellent place to start your Computer Science studies. If you have covered binary numbers at KS3 or in previous courses, you may find that you move through this topic quicker than others.
Keep an eye out for the tables in each lesson which show what you are expected to know for the CIE iGCSE Computer Science exam as this may be different from other exam boards.
| Topic | I should be able to… |
|---|---|
| 1.1 | Understand how and why computers use binary to represent all forms of data |
| Understand the denary, binary and hexadecimal number systems | |
| Convert between (i) positive denary and positive binary (ii) positive denary and positive hexadecimal (iii) positive hexadecimal and positive binary | |
| Understand how and why hexadecimal is used as a beneficial method of data representation | |
| Add two positive 8-bit binary integers | |
| New for 2023 | Understand the concept of overflow and why it occurs in binary addition |
| New for 2023 | Perform a logical binary shift on a positive 8-bit binary integer and understand the effect this has on the positive binary integer |
| New for 2023 | Use two’s complement to represent positive and negative 8-bit binary integers |