... Commodore BASIC suffered from four major performance issues:

- It stored numbers as text in the source, and had to parse numbers every time they were used.
- Program lines are stored as singly-linked lists, so if it branched back to a line earlier in the program, `goto` and `gosub` had to start at the top of the program and find the target line, one line at a time. Forward branches searched one line at a time, starting from the executing line.
- Variables were stored in a singly linked list, so it would iterate through the list, one by one, until it found the referenced variable.
- All computations are done as software floating point. Integer variable updates would be converted to floating point, have the computation performed, then converted back to integer.
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