Architecture encompasses the process, artifacts and high-level structure of a solution.
Architecture tag tends to cover a broad range of topics related to architecture, but mostly focuses on issues related to software.
As a Process
Architecture looks to gather information and make informed decisions regarding the nature of the solution. This specifically includes:
- Interaction with various stakeholders.
- Establishing the relative importance of various System Quality Attributes which will drive the architecture.
- Evaluating different options against requirements (which can be both project specific and enterprise wide).
As a Role
Architecture covers the entire domain of software / information systems, and is composed of many specific roles that deal with the diverse complexity of that domain.
- Enterprise Architects who deal with the top most strategic level of (often business orientated) architecture.
- Solution Architects who tend to work on project specific work, and whom cover a very broad range of technology.
- Software Architects who tend to work very much as Solution Architects but with a specific focus on Software.
These roles tend cover a broad spectrum of disciplines, and are supported by the follow roles which tend to have a much more specific focus and whom can cover both project specific work and enterprise wide concerns (such as tool selection):
- Infrastructure and Network Architects who deal with those respective areas (see http://serverfault.com).
- Data Architects who deal with all aspects relating to data including management, quality and re-use. Data Architects also deal with Business Intelligence.
- Security Architects who focus on all aspects of security.
This list isn't exhaustive, other common architecture roles include Application Architect and Technical Architect.