I'm trying to searching the most important information about evaluation...

Two main types of evaluation:
-Formative evaluation is done at different stages of development to check
that the product meets users' needs
-Summative evaluation assesses the quality of a finished product

What to evaluate
-Iterative design & evaluation is a continuous
process that examines:
–Early ideas for conceptual model
–Early prototypes of the new system
–Later, more complete prototypes
Designers need to check that they
understand users' requirements

When to evaluate
Throughout the design
From the first descriptions, sketches etc. of user needs through to the final product
Design proceeds through iterative cycles of: Design – test ­redesign
Evaluation is a key ingredient for a
successful design