Centenary of Lithuanian Organizations (Lithuania 2020)

Souvenir Sheet Centenary of Lithuanian Organizations it reflects the thematic directions:

An anniversary is the date on which an event took place or an institution was founded in a previous year, and may also refer to the commemoration or celebration of that event. For example, the first event is the initial occurrence or, if planned, the inaugural of the event. One year later would be the first anniversary of that event. The word was first used for Catholic feasts to commemorate saints. Most countries celebrate national anniversaries, typically called national days. These could be the date of independence of the nation or the adoption of a new constitution or form of government. The important dates in a sitting monarch's reign may also be commemorated, an event often referred to as a "Jubilee".

A military, also known collectively as an armed forces, are a heavily armed, highly organized force primarily intended for warfare. Militaries are typically authorized and maintained by a sovereign state, with their members identifiable by a distinct military uniform. They may consist of one or more military branches such as an army, navy, air force, space force, marines, or coast guard. The main task of a military is usually defined as defence of their state and its interests against external armed threats.

An opera house is a theater building used for performances of opera. Like many theaters, it usually includes a stage, an orchestra pit, audience seating, backstage facilities for costumes and building sets, as well as offices for the institution's administration.

In modern politics, and history, a parliament is a legislative body of government. Generally, a modern parliament has three functions: representing the electorate, making laws, and overseeing the government via hearings and inquiries. The term is similar to the idea of a senate, synod or congress and is commonly used in countries that are current or former monarchies. Some contexts restrict the use of the word parliament to parliamentary systems, although it is also used to describe the legislature in some presidential systems (e.g., the Parliament of Ghana), even where it is not in the official name.