[3] It is located along the eastern border of Metro Manila with Rizal province, the city shares its name with the Pasig River.

A formerly rural settlement, Pasig is primarily residential and industrial, but has been becoming increasingly commercial in recent years, particularly after the construction of the Ortigas Center business district in its west.

[citation needed] Pasig was formerly part of Rizal province before the formation of Metro Manila, the national capital region of the country.

[14] However, surviving genealogical records and folk histories speak of a thriving precolonial barangay on the banks of the Bitukang Manok River (now nearly extinct and known as Parian Creek), which eventually became modern-day Pasig.

[citation needed] Among its early dwellers were Tagalogs and people from South China with origins dating back to the Ming dynasty).

[15] The first stretch of the Bitukang Manok became known as the "Pariancillo" (Estero de San Agustin), where its shoreline was once settled by ethnic Chinese and Malay merchants to trade their goods with Tagalogs until it developed up to the 1970s as the city's main public market.

Likewise, the creek contributed enormously to the economic growth of Pasig during the Spanish colonial era (1565–1898) through irrigation of its wide paddy fields, and by being the progressive center of barter trade.

The creek has been also used during the British Occupation of Manila in 1762 to 1764 by the Royal British army, under the leadership of General William Draper and Vice Admiral Sir Samuel Cornish, 1st Baronet, to transport their red troops (and also the Sepoys they've brought from East India) upstream to take over the nearby forest-surrounded villages of Cainta and Taytay.

The Sepoys backstabbed their abusive British lieutenants and sided with the combined forces of the Spanish Conquistadors (assigned by the Governor-General Simon de Anda y Salazar), local rice farmers, fisherfolk, and even Chinese traders.

After the British Invasion, the Sepoys remained and intermarried with Filipina women, and that explains the Hindu features of some of today's citizens of Pasig, especially Cainta and Taytay.

Andres Bonifacio, Emilio Jacinto and Pio Valenzuela, secretly gained access in this very creek aboard a fleet of seventeen "Bangkas" (canoes) to the old residence of a notable Valentin Cruz at Barangay San Nicolas, and formed the "Asamblea Magna" (mass meeting).

Three months later on Saturday evening, August 29, about less than 2,000 working-class Pasigueños (along with a hundred Chinese "Trabajadores" (laborers) from the failed Sangley revolts of 1639 and throughout the 17th century), armed with coconuts, machetes and bayoneted muskets (some were donated by the rich Ilustrado families, while many of those guns were looted from Spanish authorities), joined the Katipunan and made a surprise attack at the "Municipio del Gobernadorcillo" (the current site of the Pasig City Hall) and its adjacent garrison of the "Guardias Civil" (Civil Guard), situated near the border of barangays Maybunga and Caniogan.

After they had managed to successfully out-thrown the seat of Spanish government on Pasig, the Katipuneros fled immediately and advanced towards a "Sitio" located at the neighboring "Ciudad de San Juan" called "Pinaglabanan", and there they launched their second attempt to end the numerous cases of corruption made by the greedy Castilian "Encomenderos" (town officials) and "Hacienderos" (landlords), which shall be commemorated as the Battle of San Juan del Monte.

In 1939, the barrio or sitio of Ogong (Ugong Norte), which includes the present-day Libis area, was separated from Pasig to form part of the newly established Quezon City.

The worst came to the Bitukang Manok in the late 1960s when the disappearing waterway, instead of being revived was totally separated from the Marikina River, and was converted into an open sewage ditch, with its original flow now moving in reverse towards the direction of the Napindan Channel (a portion of the Pasig River bordering between the barangays Kalawaan-Pinagbuhatan and Taguig), to give way to public commercial facilities.

"[22] Another human rights advocate who was an early critic of Marcos' policies was opposition figure Jovito Salonga, a Pasig native who was elected representative of Rizal in 1961.

[28] When Marcos suspended the writ of habeas corpus in 1971, eventually declared Martial Law in September 1972, students were unable to congregate.

In Pasig, one of the prominent residences that sheltered them and allowed them to meet together was the Bahay na Tisa in Barangay San Jose.

[30] Another prominent site in Pasig which was affected by Martial Law was the Benpres Building, which was shuttered by the Philippine Constabulary when Marcos' declaration closed down all media outlets on September 23, 1972.

[31] After the fall of the dictatorship, one of the first properties to be surrendered by a Marcos crony to the PCGG was the "Payanig sa Pasig" property, at the confluence of Ortigas, Meralco and Doña Julia Vargas Avenues, whose title businessman Jose Yao Campos said he was keeping under the name of the Mid-Pasig Land Development Corp (MPLDC) in lieu of Ferdinand Marcos.

On February 4, 2006, the ULTRA Stampede, in which 71 people died, happened during the first anniversary celebration of ABS-CBN's noontime show Wowowee, because of the prizes that were to be given away.

Pasig was one of the areas struck by the high flood created by Typhoon Ondoy (Ketsana) on September 26, 2009, which affected the Ortigas Avenue and the east city side of the Manggahan Floodway.

In the first week of August 2012, intense monsoon rain caused the 2012 Philippines flooding, which affected again Pasig and particularly the National Capital Region (NCR), Calabarzon and the southwest part of Luzon.

Pasig is bordered on the west by Quezon City and Mandaluyong; to the north by Marikina; to the south by Pateros and Taguig; and to the east by the municipalities of Cainta and Taytay in the province of Rizal.

Notable developments along E. Rodriguez Jr. Avenue (C-5) include Arcovia City, The Grove by Rockwell, and Ortigas East (formerly Frontera Verde), home of the Tiendesitas market.

Bridgetowne Destination Estates, a 31-hectare (77-acre) integrated township development of Robinsons Land, has its Victor Monument and bridge connecting Pasig and Quezon City.

The tentatively-named Home of the UAAP in Bridgetowne, a partnership between the University Athletic Association of the Philippines and Akari Lighting & Technology Corp., will begin construction in 2025 and open in 2027.

That basketball court which stands today, surrounded by the Montalban Catholic Church and Cemetery, was once the railway station terminus of that particular line.

Today, the citizens are dependent on tricycles, jeepneys, taxis, UV Express, buses, and AUV's which contribute to the everyday unusual and unbearable traffic of Metro Manila.

RTU Pasig campus is established in 1994 that offered different courses in the field of Engineering, Education, Astronomy, Business and Entrepreneurship.