It is common in UK academic writing that the body of your writing starts in a general way, and then focuses on specifics. This is called general-specific structure or deductive structure.
This is a progression of ideas from general statements to specific detail, and it applies to paragraphs and essays as a whole.
This general-specific pattern means that the first part of the essay begins with:
The remainder of your writing often looks at the specifics:
Here is an example of a paragraph from an Engineering essay that moves from a general to specific point in one paragraph through the use of an illustrated example. Read the paragraph and notice how ideas move from general to specific. The darker colours represent general and the lighter more specific: