On a Unix/Linux shell, which single character is used to separate multiple commands on the same command line so they run sequentially?

Introduction / Context:
Command chaining improves productivity by letting you run several commands in order without new prompts. Understanding the correct separator character avoids syntax errors and ensures the shell executes each command sequentially regardless of prior exit codes (unless you use conditional operators like && or ||).

Given Data / Assumptions:

• You are using a POSIX shell (bash, dash, zsh, etc.).
• You want commands to run one after another unconditionally.
• No special control-flow constructs are required.

Concept / Approach:
The semicolon '; ' separates commands on a single line. For example, 'mkdir build; cd build; make' executes three commands in sequence. Alternatives such as '&&' and '||' are conditional separators based on success or failure; they are not single-character plain separators like ';'.

Step-by-Step Solution:

Verification / Alternative check:
Run a short chain and observe that each command executes in order. Insert an intentional failure to see that, unlike '&&', a semicolon does not prevent the next command from running.

Why Other Options Are Wrong:

• #: Begins a comment in many shells; everything after is ignored.
• $: Used for variable expansion/prompt indicator; not a separator.
• :: A builtin no-op in some shells, not a command separator for sequences.
• None of the above: Incorrect because ';' is correct.

Common Pitfalls:
Forgetting spaces where required by certain commands, or mixing separators with unquoted special characters that the shell expands unexpectedly.

Final Answer:
;