证券交易是指通过买卖证券来实现投资和融资的一种方式。证券交易按照不同的特征可以分为多种方式，包括公开市场交易、场外交易和交易所交易。

公开市场交易是指证券交易在公开市场进行的方式。公开市场是指由政府或其他机构组织并公开向市场参与者提供买卖证券的场所。在公开市场交易中，买卖双方通过经纪商或交易平台进行交易，交易价格由市场供求决定。常见的公开市场交易包括股票交易和债券交易。股票交易是指投资者通过证券交易所或其他交易平台买卖股票，而债券交易是指投资者买卖债券以获得固定收益。

Public market trading refers to the way in which securities are traded in the public market. Public markets are organized by governments or other institutions and provide a venue for market participants to buy and sell securities openly. In public market trading, buyers and sellers transact through brokers or trading platforms, and the transaction prices are determined by market supply and demand. Common forms of public market trading include stock trading and bond trading. Stock trading involves the buying and selling of stocks by investors through a securities exchange or other trading platforms, while bond trading refers to investors buying and selling bonds to earn fixed income.

场外交易是指证券交易在场外进行的方式。场外交易也被称为非交易所交易。在这种交易方式中，买卖双方通过私下协商达成交易，并没有像交易所那样的市场集中交易的场所。场外交易通常适用于规模较小、流动性较低的证券，例如某些公司的非上市股份或其他非标准化的金融产品。场外交易的价格和交易细节通常由参与交易的双方协商确定。

Over-the-counter (OTC) trading refers to securities trading conducted off-exchange. OTC trading is also known as non-exchange trading. In this form of trading, buyers and sellers reach an agreement through private negotiations, without a centralized marketplace like an exchange. OTC trading is typically applicable to smaller-scale and less liquid securities, such as shares of unlisted companies or other non-standardized financial products. The price and transaction details in OTC trading are usually determined through negotiations between the participating parties.

交易所交易是指证券交易在专门的交易所进行的方式。交易所是一个中央市场，提供了一个集中买卖证券的场所，并建立了一系列的规则和制度来保护投资者的权益。在交易所交易中，买卖双方通过交易所的撮合机制进行交易，交易价格由市场供求决定。交易所交易通常适用于规模较大、流动性较高的证券，如股票、期货和期权等。

Exchange trading refers to securities trading conducted on specialized exchanges. An exchange is a central marketplace that provides a venue for centralized buying and selling of securities, and establishes a series of rules and regulations to protect the rights of investors. In exchange trading, buyers and sellers transact through the exchange's matching mechanism, and the transaction prices are determined by market supply and demand. Exchange trading is typically applicable to larger-scale and more liquid securities, such as stocks, futures, and options.

总结起来，证券交易方式的分类主要包括公开市场交易、场外交易和交易所交易。这些不同的交易方式适用于不同类型的证券和投资者，提供了多样化的交易选择。投资者可以根据自身需求和风险偏好选择适合自己的交易方式，以实现投资目标和获得资本增值。

To summarize, the classification of securities trading methods mainly includes public market trading, OTC trading, and exchange trading. These different trading methods are applicable to different types of securities and investors, providing diversified trading options. Investors can choose the trading method that suits their needs and risk preferences to achieve their investment goals and obtain capital appreciation.