A continuous and democratic association of workers, voluntarily created by themselves to improve and protect their economic and general social conditions. Sidney and Beatrice Webb in 1920 defined a trade union as: "a continuous association of wage earners for the purpose of maintaining and improving the conditions of their working lives". The trade union is essentially a creature of conflict, and will always be on fertile ground in an environment of industrial conflict. Primarily, the trade union represents its members in determining wages and working conditions and in addressing their day-to-day problems (grievances) with management. This representation is effected through the collective bargaining and grievance handling processes. Generally, trade unions in a country must operate within the confines of some form of 'Trade Union" legislation. This legislation will among other things, set out the rights and obligations, and offer some insights into what form (s) the union can take. In many countries, the legislation permits for persons other than 'workers' to form trade unions. Because of this, there can be the following three broad categories of trade unions: (a) Workers' Union an association of 'workers'; (b) Employers' Union an association of employers; (c) Professionals' Union an association of professionals. There are various types of workers' unions, some important ones being the: (a) Craft Union a particular craft or skilled grouping. (b) Industrial Union a particular industry or sector grouping. (c) General Union not restricted to any particular grouping. (d) Company Union/Enterprise Union restricted to employees of a particular company