Computer science: Bash scripting: a few points

Self-tutoring about Bash scripting: the tutor mentions a few hints.

The following is according to my understanding.

It’s been a while since I’ve done any Bash scripting, so I had to re-learn a few details.

Within brackets, such as ones that denote a test or evaluation, it seems one needs a space on either side of the content.

In an opposite sense, with an equal assignment to a variable, spaces aren’t allowed either side of the equal sign.

It seems that, if one puts in or removes a space, then the text changes colour, a meaningful change has happened.

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