Shorelines can be classified based on various factors such as their formation, geological features, and the processes that shape them. The classification of shorelines helps in understanding their characteristics, dynamics, and the forces that influence them. Here, we will discuss the method of classification and briefly explain some major shoreline features.

1. Classification Method:
Shorelines can be classified into three main categories based on their formation:
1. Primary Shorelines: These are the shorelines that are formed by tectonic activities, such as the uplift or subsidence of landmasses. They include coastlines formed along fault lines or due to volcanic activities.
2. Secondary Shorelines: These shorelines are formed by the action of erosional forces like waves, wind, and glaciers. They include coastlines formed by wave erosion, deposition, and abrasion.
3. Tertiary Shorelines: These are the shorelines that are formed due to the influence of human activities such as construction of harbors, jetties, or artificial land reclamation.

2. Major Shoreline Features:
Shorelines exhibit various features that are a result of geological processes and the interaction between land and water. Some of the major shoreline features include:

- Cliffs: These are steep, vertical or near-vertical walls of rock that are commonly found along primary shorelines. Cliffs are formed due to tectonic activities or erosional processes.

- Beaches: Beaches are depositional landforms that consist of loose sediment such as sand, gravel, or pebbles. They are formed by the deposition of sediments carried by waves and currents.

- Deltas: Deltas are formed at the mouths of rivers where they deposit sediments into a standing body of water, such as a lake or an ocean. Deltas are characterized by their triangular shape and are often rich in fertile soil.

- Estuaries: Estuaries are partially enclosed coastal bodies of water where freshwater from rivers and saltwater from the ocean mix. They are often characterized by intricate networks of channels, islands, and marshes.

- Sea Caves and Arches: Sea caves and arches are formed by the erosive power of waves. Over time, waves erode weaknesses in the rock, creating caves and arches along the shoreline.

- Barrier Islands: Barrier islands are long, narrow offshore landforms that run parallel to the mainland. They are formed by the deposition of sediments by waves and currents, and they act as natural buffers protecting the mainland from the open ocean.

In conclusion, shorelines can be classified based on their formation and characteristics. Primary, secondary, and tertiary shorelines are classified based on their formation processes. Major shoreline features include cliffs, beaches, deltas, estuaries, sea caves and arches, and barrier islands. Understanding these features and their classification helps in comprehending the dynamic nature of shorelines and their significance in coastal ecosystems.