It specifically involves evaluators examining the interface and judging its compliance with recognized usability principles (the "heuristics").
The main goal of heuristic evaluations is to identify any problems associated with the design of user interfaces.
Quite often, usability problems that are discovered are categorized—often on a numeric scale—according to their estimated impact on user performance or acceptance.
The simplicity of heuristic evaluation is beneficial at the early stages of design and prior to user-based testing.
This usability inspection method does not rely on users which can be burdensome due to the need for recruiting, scheduling issues, a place to perform the evaluation, and a payment for participant time.
Although heuristic evaluation can uncover many major usability issues in a short period of time, a criticism that is often leveled is that results are highly influenced by the knowledge of the expert reviewer(s).
As a general rule of thumb, there are researched frameworks involved to reduce bias and maximize findings within an evaluation.
Heuristic evaluation must start individually before aggregating results in order to reduce group confirmation bias.
Ben Shneiderman's book was published a few years prior to Nielsen, Designing the User Interface: Strategies for Effective Human-Computer Interaction (1986) covered his popular list of the, "Eight Golden Rules".